Modulation system for modulating data onto a carrier signal with offsets to compensate for doppler effect and allow a frequency synthesizing system to make steps equal to channel bandwidth

ABSTRACT

A method and system for modulating data onto a carrier signal in a plurality of channels, each of the channels having a channel bandwidth, can be created for use in any two-way satellite communication system or other wireless communication application where frequency hopping with or without Doppler compensation is desired. The system preferably includes a digital modulator that outputs a modulated baseband signal, an intermediate frequency modulator that receives the modulated baseband signal and outputs an intermediate frequency signal derived from the modulated baseband signal, a frequency synthesizing system that outputs a synthesized intermediate frequency signal to the intermediate frequency modulator, and a circuit (numerically controlled oscillator) connected to the digital modulator which provides a signal to the digital modulator. This signal has a frequency including an offset that allows the frequency synthesizing system and intermediate frequency modulator to make frequency steps equal to the channel bandwidth. The offset can also include a small offset that compensates for the Doppler effect.

FIELD OF THE INVENTION

The present invention relates to the field of signal modulation. Moreparticularly, the present invention relates to the field of two-waysatellite communication systems in which modulated signals carry data.

BACKGROUND OF THE INVENTION

The K_(a)-band of the electromagnetic spectrum is the radio frequencyband between about 17 and 36 GHz. This upper portion of the microwaverange is used primarily for satellite communication. Many two-waysatellite communication systems transmit and receive data in theK_(a)-band. However, other two-way satellite communication systemstransmit and receive data in various other bands such as the C-band(3.7–6.4 GHz) and the K_(u)-band (11–15 GHz), for example. Futuresystems may use higher frequencies (e.g., 60 GHz).

Modulation and upconversion are essential methods used in wirelesscommunication systems, including two-way satellite communicationsystems. Upconversion is the translation of a signal's frequency frombaseband, or the original frequency before modulation, to a higherfrequency. The signal is then transmitted at this higher frequency.Upconversion is done because most antennas can only receive signals thathave short wavelengths. Frequency is the inverse of wavelength.Therefore, the higher the frequency a signal has, the shorter itswavelength.

Modulation is a method used to transmit and receive digital signals. Byvarying the phase of the transmitted signal, for example, informationcan be conveyed. This type of modulation is called phase-shift keying(PSK). There are several schemes that can be used to accomplish PSK. Thesimplest method uses only two signal phases: 0 degrees and 180 degrees.The digital signal is broken up time wise into individual bits (binarydigits—zeros and ones). The state of each bit is determined according tothe state of the preceding bit. If the phase of the wave does notchange, then the signal state stays the same (low or high). If the phaseof the wave changes by 180 degrees—that is, if the phase reverses—thenthe signal state changes (from low to high, or from high to low).Because there are two possible wave phases, this form of PSK issometimes called Binary Phase Shift Keying (BPSK).

A more complex form of PSK is called Quadrature Phase Shift Keying(QPSK). QPSK modulation employs four wave phases and allows binary datato be transmitted at a faster rate per phase change than is possiblewith BPSK modulation. In QPSK modulation, the signal to be transmittedis first separated into two signals: the In-phase (I) signal and theQuadrature (Q) signal. The I and Q signals are orthogonal, or 90 degreesout of phase. Thus, they are totally independent and do not interferewith each other. Each signal can then be phase shifted independently.Both the I and Q signals have two possible phase states. Combining thepossible states for the I and Q signals results in four total possiblestates. Each state can then represent two bits. Thus, twice theinformation can be conveyed using QPSK modulation instead of BPSKmodulation. For this reason, QPSK modulation is used in many two-waysatellite communication systems.

For any two-way satellite communication system using a QPSK modulatorand upconverter, there are a number of competing design goals. First,the system should have low phase noise. Phase noise is a result ofrapid, short-term, random fluctuations in the phase of a wave and iscaused by instabilities found in oscillators.

Low levels of spurious emissions (also called spurious noise) are alsodesirable. Spurious emissions are emissions on a frequency orfrequencies which are outside the necessary bandwidth of thetransmitting signal, but still within the band. These emissions may bereduced without affecting the corresponding transmission of information.Spurious emissions include intermodulation distortion and harmonicdistortion. Intermodulation distortion is a result of emissions on thesum and difference frequencies of the fundamental frequencies of thetransmitted signal. Harmonic distortion is a result of emissions onfrequencies that are not present in the input signal. Both distortionsare caused by nonlinearities in the devices used to modulate thesignals.

Another design goal is that there should also be a large frequencyhopping range. Frequency hopping is a modulation technique that involvesthe repeated switching of frequencies during transmission. Frequencysynthesizers generate the frequencies that are to be hopped to. A smallfrequency settling time, or the time it takes for the frequencysynthesizer to lock into the new frequency, is also desirable. In thecase of an example K_(a)-band two-way satellite communication system,there are four 125 MHz bands over which the frequency synthesizer mustoperate. Each band is partitioned into a number of channels. In oneexample, a class A two-way satellite communication system is defined tohave 175 channels per band. In another example, a class B two-waysatellite communication system is defined to have 35 channels per band.The frequency synthesizer must preferably be able to hop to the centerfrequency of each channel within a few nanoseconds.

A very fine frequency accuracy and step size is preferably required tocompensate for, or correct, the Doppler effect. The Doppler effectrefers to the phenomenon of a signal's frequency being affected by therelative motion of the transmitter and receiver. When the signal sourceis approaching the observer, for example, the signal's frequencyincreases. Because satellites are constantly moving, the modulator andupconverter must preferably compensate for the Doppler effect. TheDoppler frequency may range from −160 Hz to +160 Hz in two-waygeostationary satellite communication.

Finally, there should be small amplitude and group delay variationacross the hopping band. Amplitude variation happens when the signal hasdifferent amplitudes across the band. Group delay is the rate of changeof the total phase shift with respect to angular frequency through atransmission medium. It is desirable to maintain both a constantamplitude and group delay across the hopping band.

Currently, the K_(a)-band upconversion entails a multi-stage conversionprocess. First, baseband QPSK I,Q streams are modulated and thenupconverted to an Intermediate Frequency (IF) in the L-band range (e.g.,1.7–2.2 GHz). This conversion is performed by in an Indoor Unit (IDU).The signal is then upconverted again and amplified to 29.5 to 30.0 GHzin an Outdoor Unit (ODU) located at the terminal's antenna. Theupconversion is then complete and the signal is ready for transmission.To meet frequency accuracy requirements, the Local Oscillators (LO's) inall the upconversion stages can be phase locked to a single reference(e.g., a reference locked to the stable satellite payload oscillatoravailable in the satellite downlink signal).

The IDU and the ODU are connected via some type of cable, for exampleRG-6. This type of cable performs well and has relatively small losses(10–15 dB per 100 feet) at frequencies of 1.7–2.2 GHz. In addition, RG-6cable is easy to procure because this IF range is a common range usedcurrently with digital satellite television set-tops. Thus, there aremany RG-6 suppliers. However, other kinds of cables could also possiblybe used to connect the IDU and the ODU.

Because of the various competing design goals mentioned above, there aremany tradeoffs that are made in the IDU modulator and IF upconverterdesign. For example, single analog upconversion from baseband to IF canachieve low spurious and phase noise, large hopping range, and smallamplitude and delay variation. However, these gains are achieved at theexpense of a large frequency settling time and large step sizes.Direct-Digital Synthesis (DDS) can be used in these analog synthesizersto improve settling time and decrease step size but can require costlyfiltering to achieve low spurious noise. Heterodyne architectures (e.g.,double analog upconverters) can be used to reduce the spurious noise.However, such architectures require complex analog bandpass filteringthat risks increasing amplitude and group delay variation.

An alternate approach to meet the design goals above is to use anall-digital upconverter to accomplish the upconversion from baseband toIF. This, however, forces the Digital-to-Analog Converter (DAC) tooperate at a very high sampling rate (e.g., greater than 1.7–2.2 GHz).DACs that operate at these high sample rates are currently difficult todesign and are not cost-effective for most applications.

Digital upconversion can be used in conjunction with analog IFupconversion to achieve fast hopping and small step size over a limitedbandwidth. Digital process technologies (CMOS) enable current designs ofNumerically Control Oscillators (NCOs) to economically run at 200–400MHz clock frequencies to achieve frequency hopping bandwidths of 50–100MHz. When combined with analog upconversion, however, there can beserious spurious emission problems. For example, a digital I/Qupconversion to a center frequency of f_(d)=10 MHz requiring analogupconversion to 1.7 GHz utilizes an analog LO of f_(VCO,IF)=1.71 GHz or1.69 GHz. DAC and analog mixer nonlinearities and unbalances inducespurious noise (intermodulation distortion) at IF at frequencies of±nf_(VCO,IF)±mf_(d) for integers m and n. It is difficult tosufficiently filter (reject) intermodulation products at multiples of 10MHz from the desired carrier frequency.

Another problem with using digital upconversion in conjunction withanalog IF upconversion has to do with the compensation of the Dopplereffect. A prior solution included compensating for the Doppler effect inthe analog IF upconversion stage by slightly varying f_(VCO,IF). This isdifficult and costly because Doppler compensation requires very finefrequency accuracy and very fine step size. Varying f_(VCO,IF) alsoinduces spurious noise at frequencies in adjacent channels. AdjacentChannel Emissions (ACE) specifications are stringent at large offsetsfrom the desired carrier frequency and more lenient close to the signalbandwidth. Thus, the increased spurious noise in adjacent channels dueto Doppler compensation in the analog IF upconversion stage results inadditional necessary filtering that is difficult and expensive. Thus, ina combined digital/analog modulator and upconverter used in the IDU,there is a need in the art for a method and system that compensate forthe Doppler effect while avoiding out of channel spurious noise and notrequiring an analog IF frequency synthesizer with very fine frequencyaccuracy and very fine step size.

In between each of the four 125 MHz bands, there is a guard band. Aguard band is a frequency band that is deliberately left vacant betweentwo bands to provide a margin of safety against mutual interference. Inmany two-way satellite communication systems, the guard band's width isnot a multiple of the channel widths. This poses a problem in the designof the analog IF frequency synthesizer. In tuning to a particularchannel in one band and then hopping to a different channel in anotherband, the frequency synthesizer skips over the guard band. A traditionalfrequency synthesizer needs a small step size (e.g., 2.5 kHz) toaccomplish this. This results in an undesirably high phase noise. Thus,in a digital combined with analog modulator and upconverter used in theIDU, there is a need in the art for a method and system that allow ananalog IF frequency synthesizer to tune to different channels whileskipping over the guard bands with a large enough step size that willmaintain the phase noise within acceptable levels.

As used hereafter and in the appended claims, the term “two-waysatellite communication systems” will be used to refer expansively toall possible two-way satellite communication systems and other wirelesscommunication applications in any band where frequency hopping with orwithout Doppler compensation is desired.

SUMMARY OF THE INVENTION

In one of many possible embodiments, the present invention provides amodulation system for modulating data onto a carrier signal in aplurality of channels, each of the channels having a channel bandwidth.The system preferably includes a digital modulator that outputs amodulated baseband signal, an intermediate frequency modulator thatreceives the modulated baseband signal and outputs an intermediatefrequency signal derived from the modulated baseband signal, a frequencysynthesizing system that outputs a synthesized intermediate frequencysignal to the intermediate frequency modulator, and a circuit connectedto the digital modulator which provides a signal to the digitalmodulator. The signal has a frequency including an offset that allowsthe frequency synthesizing system and intermediate frequency modulatorto make frequency steps equal to the channel bandwidth.

In another embodiment, the present invention provides a modulationsystem for modulating data onto a carrier signal in a plurality ofchannels, each of the channels having a channel bandwidth. The systempreferably includes a digital modulator that outputs a modulatedbaseband signal, an intermediate frequency modulator that receives themodulated baseband signal and outputs an intermediate frequency signalderived from the modulated baseband signal, a frequency synthesizingsystem that outputs a synthesized intermediate frequency signal to theintermediate frequency modulator; and a circuit connected to the digitalmodulator which provides a signal to the digital modulator. The signalhas a frequency including an offset that compensates for Doppler effectin transmission of the carrier signal.

In another embodiment, the present invention provides a method formodulating data onto a carrier signal in a plurality of channels, eachof the channels having a channel bandwidth. The method preferablycomprises providing a signal to a digital modulator that modulates abaseband signal. The signal has a frequency that includes an offset thatallows a frequency synthesizing system and intermediate frequencymodulator to make frequency steps equal to the channel bandwidth.

In another embodiment, the present invention provides a method ofmodulating data onto a carrier signal in a plurality of channels, eachof the channels having a channel bandwidth. The method preferablycomprises providing a signal to a digital modulator that modulates abaseband signal. The signal has a frequency that includes an offset thatcompensates for Doppler effect in transmission of the carrier signal.

Another embodiment of the present invention provides a system formodulating data onto a carrier signal in a plurality of channels, eachof the channels having a channel bandwidth. The system comprises adigital modulator that outputs a modulated baseband signal, anintermediate frequency modulator that receives the modulated basebandsignal and outputs an intermediate frequency signal derived from themodulated baseband signal, a frequency synthesizing system that outputsa synthesized intermediate frequency signal to the intermediatefrequency modulator, and a means for generating a signal input to thedigital modulator, the signal having a frequency including an offsetthat allows the frequency synthesizing system and the intermediatefrequency modulator to make frequency steps equal to the channelbandwidth.

Another embodiment of the present invention provides a system formodulating data onto a carrier signal in a plurality of channels, eachof the channels having a channel bandwidth. The system comprises adigital modulator that outputs a modulated baseband signal, anintermediate frequency modulator that receives the modulated basebandsignal and outputs an intermediate frequency signal derived from themodulated baseband signal, a frequency synthesizing system that outputsa synthesized intermediate frequency signal to the intermediatefrequency modulator, and a means for generating a signal input to thedigital modulator, the signal having a frequency including an offsetthat compensates for Doppler effect in transmission of the carriersignal.

Additional advantages and novel features of the invention will be setforth in the description which follows or may be learned by thoseskilled in the art through reading these materials or practicing theinvention. The advantages of the invention may be achieved through themeans recited in the attached claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate preferred embodiments of thepresent invention and are a part of the specification. Together with thefollowing description, the drawings demonstrate and explain theprinciples of the present invention. The illustrated embodiments areexamples of the present invention and do not limit the scope of theinvention.

FIG. 1 is a basic block diagram of a multi-stage modulator andupconverter that is used in a two-way satellite communication system andthat could be used to implement the present invention.

FIG. 2 is a detailed block diagram of a digital modulator and a IFmodulator with which the present invention could be practiced.

FIG. 3 illustrates a configuration whereby a numerically controlledoscillator (NCO) generates a frequency offset near baseband that allowsfor a large frequency step size for the frequency synthesizers andcorrects the Doppler effect according to an embodiment of the presentinvention.

FIG. 4 shows the specific components of the frequency synthesizers thatcould be used to implement the present invention.

FIG. 5 shows the divisions of the frequency bands which are used bytwo-way satellite communication systems.

FIG. 6 shows the frequency spectrum of a transmitted signal and itsassociated spurious noise in an exemplary two-way satellitecommunication system under the embodiments of the present invention.

FIG. 7 shows the frequency spectrum of a transmitted signal and itsassociated spurious noise in an exemplary two-way satellitecommunication system where the embodiments of the present invention arenot used.

Throughout the drawings, identical reference numbers designate similar,though not necessarily identical, elements.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a method and system whereby a very fasttuning QPSK modulator and upconverter can be used in two-way satellitecommunication systems to transmit data while meeting the typical two-waysatellite communication system design goals of low phase noise, lowspurious emissions levels, large frequency hopping range, smallfrequency settling time, fine frequency accuracy and step size tocorrect the Doppler effect, and small amplitude and group delayvariation across the hopping band. Such design goals could apply to anyand all two-way satellite communication systems as well as to otherapplications where cost-effective wireless communication is desiredusing the K_(a)-band. The present invention, therefore, applies to anyand all two-way satellite communication systems as well as to otherapplications where wireless communication is desired using theK_(a)-band.

Additionally, the present invention provides a method and system ofcorrecting the Doppler effect without introducing out-of-channelspurious emission levels that exceed Adjacent Channel Emissions (ACE)specifications. Under the principles of the present invention, as willbe explained in more detail below in connections with FIG. 3, theDoppler effect is corrected by slightly varying the frequency producedby the Numerically Controlled Oscillator (NCO) in the digitalupconversion stage.

The present invention also provides a method and system of generating alarge analog IF frequency synthesizer step size so that the phase noiseis low and within the deemed acceptable levels as specified by wirelesscommunication regulatory bodies. Under the principles of the presentinvention, as will be explained in more detail below, an offset isgenerated by the NCO in the digital upconversion stage that allows theanalog IF frequency synthesizer step size to be large. This offset iscombined with the frequency offset required to correct the Dopplereffect into one frequency offset.

Using the drawings, the preferred embodiments of the present inventionwill now be explained.

FIG. 1 is a basic block diagram of a multi-stage modulator andupconverter that is used in a two-way satellite communication system andthat could be used to implement the present invention. Baseband QPSK I(101) and Q (102) signals are modulated and upconverted to anintermediate frequency (IF), f_(IF), in the IDU (100). This modulationand upconversion is done in two stages within the IDU (100). First, theI (101) and Q (102) signals are modulated digitally with a digitalmodulator (103). A more detailed description of the digital modulator(103) will be given below in connection with FIG. 2. The digitalmodulator (103) upconverts the I (101) and Q (102) signals from basebandto a frequency, f_(d). This frequency, f_(d), is preferably much lowerthan both the transmitted signal channel bandwidth and the IF, f_(IF).An example of a possible, but not exclusive, value for f_(d) is lessthan 10–20 percent of the transmitted signal channel bandwidth. This keyconstraint on f_(d) eases many aspects of the upconverter andsynthesizer designs as will be described below in more detail inconnection with FIG. 6. The output signals of the digital modulator(103) each contain modulated I (101) and Q (102) signals. As explainedbefore, the I (101) and Q (102) signals are orthogonal, or 90 degreesout of phase. Thus, they are totally independent and can be combinedinto one signal and then later separated without the loss of information

The resulting two output signals of the digital modulator (103) are thenconverted from digital signals to analog signals. This conversion isdone using a Dual DAC (104). Because the digital to analog conversion isdone at a relatively low frequency, the Dual DAC (104) can be easilydesigned and is cost-effective for most applications.

If, on the other hand, a digital modulator (102) is used without theanalog IF modulator (105) (i.e. the IF modulator block (105) is removedfrom the block diagram of FIG. 1) to upconvert to the IF, f_(IF), theconversion from digital to analog would need to take place at a muchhigher frequency (e.g., 1.7–2.2 GHz). This would result in the Dual DAC(104) having to operate at this higher frequency of 1.7–2.2 GHz.Currently, such Dual DAC's (104) are difficult and costly to design andproduce.

Once the two output signals of the digital modulator (103) have beenconverted from digital signals to analog signals with the Dual DAC(104), they are again modulated, this time with an analog IF modulator(105). A more detailed description of the IF modulator (105) will begiven below in connection with FIG. 2. The IF modulator (105) modulatesthe two output signals of the digital modulator (103) and then combinesthe two signals into one signal. This combined signal is upconverted bythe IF modulator (105) from the frequency, f_(d), to the IF, f_(IF). TheIF, f_(IF), is within, but not limited to, the L-band range (e.g.,1.7–2.2 GHz). This range is preferable because it is high enough thatthe ODU (106) upconversion will allow filtering of the ODU (106) localoscillator (LO).

The signal is then fed from the IDU (100) to the ODU (106) via aconnecting cable (107). The connecting cable (107) is preferably onewith low loss. An example of a suitable connecting cable (107) is RG-6cable, currently used with many other applications, such as digitalsatellite television set-tops. The ODU (106) is located at thetransmitting terminal's antenna. The ODU (106) modulates the signalreceived from the IDU (100) and upconverts it to the transmit frequency,f_(TX). The transmit frequency, f_(TX), is between 29.5 and 30 GHz,frequencies for operation within the K_(a)-band. Once the signal hasbeen upconverted to the frequency f_(TX), it is ready for transmission.

A more detailed description of the digital modulator (103), analog IFmodulator (105), and the circuitry in between the two modulationstages—all or some of which might be used to implement the presentinvention—will now be given using the detailed block diagram of FIG. 2.

FIG. 2 shows the detailed block diagram of the digital modulator (103)and the IF modulator (105). The digital modulator (103) can beimplemented using a variety of methods. Possible methods of the digitalmodulator (103) implementation include software-defined digital signalprocessing chips (DSPs), field-programmable gate arrays (FPGAs),application-specific integrated circuits (ASICs), and other types ofintegrated circuits (ICs).

The components of the digital modulator (103), shown in FIG. 2, will nowbe explained.

A numerically controlled oscillator (NCO) (201) generates two signalscentered at a frequency ω_(d): sin ω_(d) and cos ω_(d). The frequency,ω_(d), refers to the same frequency as does the frequency, f_(d). Theonly difference is that cod is expressed in radians and f_(d) isexpressed in Hertz. Thus, as used hereafter and in the appended claims,ω_(x) refers to the same frequency as does f_(x), where ‘x’ is anarbitrary subscript.

As shown in FIG. 2, the I signal (101) and the cos ω_(d) signal aremultiplied with a multiplier (200 a). The Q signal (102) and the sinω_(d) signal are also multiplied using another multiplier (200 b). Theresulting products from multipliers (200 a) and (200 b) are then addedwith an adder (202 a). The adder blocks (202 a,b,c) are designed toperform either addition or subtraction and can be programmed to performeither operation. The resulting signal contains both the I (101) and Q(102) signals and is I cos ω_(d)+Q sin ω_(d).

Simultaneously, the I signal (101) and the sin ω_(d) signal aremultiplied with a multiplier (200 c). The product of the Q signal (102)and the cos ω_(d) signal, obtained by using another multiplier (200 d),is subtracted, using another adder (202 b), from the result of themultiplier (200 c). The resulting signal also contains both the I (101)and Q (102) signals and is I sin ω_(d)−Q cos ω_(d).

Both output signals of the digital modulator (103), I cos ω_(d)+Q sinω_(d) and I sin ω_(d)−Q cos ω_(d), are input into Dual DACs (104 a,b).Depending on the application and method of implementation of the digitalmodulator (103), a certain amount of bits of the digital modulator (103)output signals are output at a given instant. An example, as shown inFIG. 2, would be that the output signals arrive at the dual DACs (104a,b) in 8-bit increments.

The circuitry found between the digital modulator (103) and the analogIF modulator (105) will now be explained using FIG. 2.

As explained in connection with FIG. 1, Dual DACs (104 a,b) convert thedigital output signals from the digital modulator (103) to analogsignals. The Dual DACs (104 a,b) are controlled with an external clocksignal (203). This clock signal (203) determines when the Dual DACs (104a,b) sample and then hold the two output signals of the digitalmodulator (103). This clock signal (203) is generated by dividing thereceive symbol clock, f_(SYM) (302; FIG. 3), by an integer using adivider block (308; FIG. 3), as shown in FIG. 3. The receive symbolclock, f_(SYM) (302), is recovered from the receiving data obtained fromthe satellite downlink signal and is a large multiple of the transmitsymbol clock in this example. This allows the transmitter to maintaintime synchronism with the satellite oscillators that generate f_(SYM).

Returning to FIG. 2, the two analog signals are then amplified by aspecific gain (205) with amplifiers (204 a,b). This is a common practicein upconverter design. Because of signal scaling and attenuation thatoccurs in the digital modulation (103) stage as well as in the Dual DACs(104 a,b), the signals need to be amplified before being modulated againby the analog IF modulator (105).

After being amplified, the two analog signals are then low pass filteredby low pass filters (LPFs) (206 a,b) to remove the possible interferencepresent at unwanted frequencies that would alias down and interfere withthe desired signal during the detection process.

The components of the analog IF modulator (105), shown in FIG. 2, willnow be explained.

An example of an analog IF modulator (105) that might be used in two-waysatellite communication systems is the RF2483 IQ modulator made by RFMicroDevice™. Other models made by the same or different companies mightalso be used. Inside the analog IF modulator (105), a 90° Phase Shifter(208) splits a carrier signal of frequency ω_(c) into two signals: sinω_(c) and cos ω_(c). The carrier frequency, ω_(c), is generated by ananalog frequency synthesizer which outputs a frequency, f_(VCO,IF)(209). The frequency synthesizer will be explained in more detail belowin connection with FIG. 3 and FIG. 4. The output from the top LPF (206a) is mixed with the cos ω_(c) signal using an analog mixer (207 a). Theresulting signal is I cos ω_(c) cos ω_(d)+Q cos ω_(c) sin ω_(d). Theother LPF's (206 b) output is mixed with the sin ω_(c) signal using asecond analog mixer (207 b). Its resulting signal is I sin ω_(c) sinω_(d)−Q sin ω_(c) cos ωd. These two signals can then be either added orsubtracted, depending on the type of IF transmit signal (f_(IF)) (210)desired. If a lower sideband signal, or a signal centered at a frequencylower than ω_(c), is desired, the two signals are added by the adder(202 c). Using common trigonometric identities, it can be shown that theresulting output of the adder (202 c) is I cos (ω_(c)−ω_(d))−Q sin(ω_(c)−ω_(d)). Likewise, if an upper sideband signal, or a signalcentered at a frequency higher than ω_(c), is desired, the two signalsare subtracted by the adder (202 c). Using trigonometric identities, itcan be shown that the resulting output of the adder (202 c) in this caseis I cos (ω_(c)+ω_(d))+Q sin (ω_(c)+ω_(d)). In the case of somesatellite communication systems, the lower sideband signal is desired.Therefore, the adder (202 c) is programmed to add. The output of theadder (202 c) is then amplified by a gain variable amplifier (204 c).This provides a good dynamic range to control the output power. Theamplified signal is the IF signal with frequency f_(IF) (210).

FIG. 3 illustrates the embodiments of the present invention. Morespecifically, the embodiments entail a method and system whereby the NCO(300) generates a frequency offset near baseband. The frequency offsetallows for a larger frequency step size than is traditionally used forthe analog frequency synthesizers (303,304). The frequency offset alsocompensates for the Doppler effect. The embodiments will be explained inmore detail below.

As shown in FIG. 3 and in the case of some K_(a)-band two-way satellitecommunication systems, there are two frequency synthesizers (303,304)that generate f_(VCO,IF) for the analog IF modulator (105). The twofrequency synthesizers (303,304) are set up in a ping-pongconfiguration. This means that while one frequency synthesizer (e.g.,303) locks into the desired frequency, the other frequency synthesizer(e.g., 304) tunes to the next desired frequency that will be hopped to.This next frequency is determined by the receiving data (301). Thesystem dwells on the first frequency for a set amount of time (e.g., 962microseconds) before a control signal, Freq_SW (413; FIG. 4), indicatesto the switch (305) to switch to the frequency generated by the secondfrequency synthesizer (304). The ping-pong configuration allows forswitching between hopping frequencies of the frequency synthesizers(303,304) within a few nanoseconds.

FIG. 4 shows the specific components of the frequency synthesizers(303,304) that could be used in conjunction with the present invention.The control signal LE1 (411) is high if the frequency command data (301)is to be input into frequency synthesizer 1 (303). Likewise, the controlsignal LE2 (412) is high if the data (301) is to be input into frequencysynthesizer 2 (304).

The components that comprise the frequency synthesizer 1 (303) will nowbe explained. The frequency synthesizer 2 (304) has identicalcomponents, most of which are not labeled with numbers in FIG. 4. Thewords “frequency synthesizer” will be used to refer to the frequencysynthesizer 1 (303) in the following explanation.

The frequency synthesizer (303) is comprised of an electronic circuitwith a voltage controlled oscillator (VCO) (400) that is constantlyadjusted to match, in phase, the frequency of an input signal. Theoutput of the VCO (400) is f_(VCO,IF). This output is fed back into afrequency synthesizer chip (401) via a power split (402). A preferredfrequency synthesizer chip (401) for such a K_(a)-band two-way satellitecommunication system is the LMX2350 chip made by NationalSemiconductor™. However, other models of frequency synthesizer chips(401) made by the same or different companies might also be used.

The frequency synthesizer chip (401) is programmable. The programmablefunctions are accessed through a serial interface. This serial interfaceis the same as the data input (301). Within the frequency synthesizerchip, there is a fraction-N frequency synthesizer (403). This takes thesignal generated by the VCO (400) and, in turn, generates a signal(e.g., a sine wave) of frequency f_(VCO,IF) that is input into a phasedetector (404). The phase detector (404) also has a second input whichis a signal with the desired step size frequency. The desired step sizefrequency for the example class A two-way satellite communication systemis 702.5 kHz. For a class B system, the desired step size frequency is3.5125 MHz. The reasoning behind the choice of these specific step sizefrequencies will be explained in more detail below in connection withFIG. 5. However, other two-way satellite communication systems mayemploy different channel bandwidths and, hence, have different stepsizes.

As shown in FIG. 4, the desired step size frequency is derived using aseries of divider blocks (405,406). The symbol clock, f_(SYM) (302), isdivided with a divide-by-7 block (405). The resulting frequency is 28.1MHz. This frequency can be divided by using another divider block (406)to give the desired comparison frequency which derives the step sizefrequency. This divider block (406) is preferably inside the frequencysynthesizer chip (401). Its dividing number can be programmed by theuser. In, for example, a class A system, the dividing number is 40because 28.1 MHz divided by 40 equals 702.5 kHz, the desired step sizefrequency. Likewise, for a class B system, the dividing number is 12,resulting in a comparison frequency of 2.34 MHz that generates a stepsize of 3.5125 MHz in the frequency synthesizers (303,304). In otherapplications, the dividing numbers of the divider blocks (405,406) canbe modified based on the desired frequency step size.

Returning to the description of the phase detector (404) of FIG. 4, thephase of the desired step size frequency is compared by the phasedetector (404) to the phase of the frequency of the signal output of thefraction-N frequency synthesizer (403). If the phases are different, thefrequency of the output signal of the fraction-N frequency synthesizer(403) is not a multiple of the frequency step size. Therefore, the phasedetector (404) outputs a signal with an increased or decreased voltagelevel signaling to the VCO (400) to either increase or decrease thefrequency of the signal which it outputs. This feedback loop continuesuntil the phases of the step size frequency and the output signal of thefraction-N frequency synthesizer (404) are identical.

As shown in FIG. 4, there is a bank of 4 different loop filters (407a–d) between the phase detector (404) and the VCO (400). Only one loopfilter (e.g., 407 a) is used at a time. The band number, class of system(either class A or class B), and desired f_(VCO,IF) determines whichloop filter (407 a–d) is to be used. A multiplexor (MUX) (408),controlled by the control signals Band_(—)1 (409) and Band_(—)0 (410),chooses which of the 4 loop filters (407 a–d) is used. The loop filters(407 a–d) are used to add stability to the system, reject spuriousnoise, and decrease the settling time. In the case of many K_(a)-bandtwo-way satellite communication systems, the frequency will hop onlywithin one band, so the MUXes (408) in each of the frequencysynthesizers (303,304) share the same control signals (409,410). Thecommands to choose which loop filter (407 a–d) that is used, in the caseof an exemplary K_(a)-band two-way satellite communication system, arelisted in Table 1.

TABLE 1 Loop Filter Selection Commands Loop Filter Band_1 Band_0f_(VCO,IF) (407a–d) # (409) (410) Class A, Band 1 2.224 to 2.101 GHz 1 00 Class A, Band 2 2.099 to 1.976 GHz 1 0 0 Class A, Band 3 1.974 to1.851 GHz 2 0 1 Class A, Band 4 1.849 to 1.726 GHz 2 0 1 Class B, Band 12.223 to 2.102 GHz 3 1 0 Class B, Band 2 2.098 to 1.977 GHz 3 1 0 ClassB, Band 3 1.973 to 1.852 GHz 4 1 1 Class B, Band 4 1.848 to 1.727 GHz 41 1

FIG. 5 will be used in conjunction with FIG. 3 to explain the firstembodiment whereby the NCO (300; FIG. 3) generates an offset that allowsfor a large frequency step size for the analog frequency synthesizers(303,304; FIG. 3). As shown in FIG. 5, there are 4 approximately 125 MHzbands (500 a–d) within which the example two-way satellite communicationsystem operates. Each band is partitioned into a set number (n) ofchannels, depending on the application. FIG. 5 shows channels 1 (501), 2(502), 3 (503), and n (504). In the case of an exemplary K_(a)-bandtwo-way satellite communication system, the bands (500 a–d) arepartitioned into either n=175 channels for Class A systems or n=35channels for class B systems.

Each channel (e.g., 501) in a particular band (e.g., 500 a) has abandwidth equal to the bandwidth of all the other channels (e.g.,502–504) in the four 125 MHz bands (500 a–d). For class A systems, thechannel (501–504) bandwidth is 702.5 KHz. For class B systems, thechannel (501–504) bandwidth is 3.5125 MHz.

In between each of the 125 MHz bands (500 a–d) there is a guard band(505). The guard band's (505) width, in the case of an exemplaryK_(a)-band two-way satellite communication system, is 2.0625 MHz. Thisbandwidth is not a multiple of the channel (501–504) bandwidths. Thus,there are not a fixed number of channel bandwidth spacings in betweenthe n'th channel (504) of one band (e.g., 500 a) and the first channelof an adjacent band (e.g., 500 b). This makes it impractical to use afrequency synthesizer (303,304) with a frequency step size equal to thechannel (e.g., 501) bandwidth's size unless a design is implemented thatgives an offset frequency of the right amount so as to allow the use ofa step size equal to the channel (e.g., 501) bandwidth's size. Bygenerating a frequency offset with the NCO (300; FIG. 3), the channel(e.g., 501) bandwidth's size can be used as the size of the step sizefor the frequency synthesizers (303,304).

The number of channels (501–504), channel (501–504) bandwidths, band(500 a–d) widths, and guard band (505) widths are dependent on theparticular application and can vary. The present invention covers allsuch possibilities.

An illustration of the procedure used to generate the frequency offsetrequired to maintain a desired step size for the frequency synthesizers(303,304) with the NCO (300; FIG. 3) will be given using the exampleclass A system. Similar procedures could be used with otherapplications. FIG. 5 will be referenced during this illustration.

A class A system has channel bandwidths of 702.5 kHz. The spacingbetween the center frequency of channel n=175 (504) of band 1 (500 a)and the center frequency of channel 1 (501) of band 2 (500 b) is 2.0625MHz+702.5 kHz=2.765 MHz. Dividing this number by the channel (e.g., 501)bandwidth (702.5 kHz) gives 3.9359. This is obviously not an integer andtherefore a step size of 702.5 kHz for the frequency synthesizers(303,304; FIG. 3) would not normally be used to frequency hop betweenthe center frequencies of the channels (501–504) across all four bands(500 a–d).

Because 2,765,000,000=(5^4)*(2^3)*7*79 (where x^y means x raised to they-th power and * is multiplication) and 702,500=(5^4)*(2^2)*3*11, thegreatest common devisor between these two numbers is (5^4)*(2^2)=2,500Hz. Thus, the frequency synthesizers (303,304; FIG. 3) would normallyneed to have a step size of 2,500 Hz to be able to hit the channel(501–504) center frequencies across the four 125 MHz bands (500 a–d).

Referring now to FIG. 3, by adding or subtracting a small frequencyoffset in the digital modulation stage (103) with the NCO (300), 702.5kHz is used as the step size for the frequency synthesizers (303,304).The amount of frequency offset depends on the band number (500 a–d; FIG.5) and can be calculated a priori for input to the NCO (300). This bandoffset is fixed for all the channels within a given 125 MHz band. Usingthis information, the NCO (300) can adjust the amount of frequencyoffset that it is providing to the amount of frequency offset needed toallow a frequency step size of 702.5 kHz.

FIG. 3 also shows that the frequency offset generated by the NCO (300)includes a frequency offset that compensates for the Doppler effect inaddition to the small fixed band offset that adjusts for hopping withina given band. By compensating for the slowly varying, low frequencyDoppler effect and band offset near baseband, the spurious noiseemissions that result from such correction lie close to the bandwidth ofthe signal. This is in contrast to other methods that use the NCO (300)to perform simultaneous Doppler correction frequency hopping across allor a subset of the channels within a band (500 a–d; FIG. 5) whileemploying analog frequency synthesizers (303,304) that center thisdigital output within the band. In other words, the spurious noise fromthe intermodulation products at ±nf_(VCO,IF)±mf_(d) only changes by the±mf_(d) factor. An example will be given with a class A system usingFIG. 6 and FIG. 7.

FIG. 6 shows a transmitted signal (600) in the frequency domain. If theNCO (300; FIG. 3) frequency offset, f_(d), is much smaller than thesignal channel bandwidth (BW) (e.g., 702.5 kHz), then spurious noise(601) near the desired IF output at F_(VCO,IF)+f_(d) will lie near thedesired channel BW and, in general, fall within a specified adjacentchannel emissions mask (602). This adjacent channel emissions mask (602)dictates the level of spurious noise (601) that can be present in anygiven channel.

However, as shown in FIG. 7, if the NCO (300; FIG. 3) performs channelfrequency hopping and Doppler correction, f_(d) changes in multiples ofthe channel BW and the intermodulation products, or spurious noise(601), will fall in adjacent channel bands and will likely exceed theadjacent channel emissions mask (602), as shown in FIG. 7. Filteringthese emissions for a large hopping f_(d) can be complicated and costlywhile no filtering is needed for the smaller f_(d) of the example givenin FIG. 6.

Returning to FIG. 3, the amount of frequency compensation that the NCO(300) must provide to compensate for the Doppler effect is extractedfrom the received data (301). In the case of an exemplary K_(a)-bandtwo-way satellite communication system, this method of Doppler effectcorrection is capable of a compensation resolution of 0.5 Hz or less.Other levels of compensation resolution could be required and achieveddepending on the application.

As FIG. 3 shows, the NCO (300) generates a frequency offset that resultsin a large frequency step size and at the same time compensates for theDoppler effect. The method of generating the appropriate offsetfrequency that results in a large frequency step size and at the sametime compensates for the Doppler effect in the class A and class Bsystems will now be explained. First, the desired f_(VCO,IF) isgenerated by programming specific values into the frequency synthesizerchip (401; FIG. 4). In the class A system, f_(VCO,IF) is represented bythe following equation: f_(VCO,IF)=f_(SYM)*(N+F/16)/280. In the class Bsystem, f_(VCO,IF) is represented by the following equation:f_(VCO,IF)=f_(SYM)*(N+F/16)/84. N and F are parameters that areprogrammed into the frequency synthesizer chip (401). As can be seen inthe given equations for f_(VCO,IF), varying N and F results in differentvalues of f_(VCO,IF).

After f_(VCO,IF) has been generated, it is then subtracted from thedesired IF frequency, f_(IF), to give the needed frequency offset thatthe NCO (300) must produce to result in the desired step size (702.5 kHzfor class A systems and 3.5125 MHz for class B systems). As an exampleof the values of F and N that are needed to generate different values off_(VCO,IF), as well as the resulting frequency offset that the NCO (300)generates, Tables 2–9 list the tuning commands for the all the channelsin the class A and class B systems.

TABLE 2 Tuning Commands for Class A - Band 1 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 1 1 29,501,382,500 2,223,617,5002,223,675,937.5 58,437.5 6 3165 1 2 29,502,085,000 2,222,915,0002,222,973,437.5 58,437.5 6 3164 1 3 29,502,787,500 2,222,212,5002,222,270,937.5 58,437.5 6 3163 1 4 29,503,490,000 2,221,510,0002,221,568,437.5 58,437.5 6 3162 1 5 29,504,192,500 2,220,807,5002,220,865,937.5 58,437.5 6 3161 1 6 29,504,895,000 2,220,105,0002,220,163,437.5 58,437.5 6 3160 1 7 29,505,597,500 2,219,402,5002,219,460,937.5 58,437.5 6 3159 1 8 29,506,300,000 2,218,700,0002,218,758,437.5 58,437.5 6 3158 1 9 29,507,002,500 2,217,997,5002,218,055,937.5 58,437.5 6 3157 1 10 29,507,705,000 2,217,295,0002,217,353,437.5 58,437.5 6 3156 1 11 29,508,407,500 2,216,592,5002,216,650,937.5 58,437.5 6 3155 1 12 29,509,110,000 2,215,890,0002,215,948,437.5 58,437.5 6 3154 1 13 29,509,812,500 2,215,187,5002,215,245,937.5 58,437.5 6 3153 1 14 29,510,515,000 2,214,485,0002,214,543,437.5 58,437.5 6 3152 1 15 29,511,217,500 2,213,782,5002,213,840,937.5 58,437.5 6 3151 1 16 29,511,920,000 2,213,080,0002,213,138,437.5 58,437.5 6 3150 1 17 29,512,622,500 2,212,377,5002,212,435,937.5 58,437.5 6 3149 1 18 29,513,325,000 2,211,675,0002,211,733,437.5 58,437.5 6 3148 1 19 29,514,027,500 2,210,972,5002,211,030,937.5 58,437.5 6 3147 1 20 29,514,730,000 2,210,270,0002,210,328,437.5 58,437.5 6 3146 1 21 29,515,432,500 2,209,567,5002,209,625,937.5 58,437.5 6 3145 1 22 29,516,135,000 2,208,865,0002,208,923,437.5 58,437.5 6 3144 1 23 29,516,837,500 2,208,162,5002,208,220,937.5 58,437.5 6 3143 1 24 29,517,540,000 2,207,460,0002,207,518,437.5 58,437.5 6 3142 1 25 29,518,242,500 2,206,757,5002,206,815,937.5 58,437.5 6 3141 1 26 29,518,945,000 2,206,055,0002,206,113,437.5 58,437.5 6 3140 1 27 29,519,647,500 2,205,352,5002,205,410,937.5 58,437.5 6 3139 1 28 29,520,350,000 2,204,650,0002,204,708,437.5 58,437.5 6 3138 1 29 29,521,052,500 2,203,947,5002,204,005,937.5 58,437.5 6 3137 1 30 29,521,755,000 2,203,245,0002,203,303,437.5 58,437.5 6 3136 1 31 29,522,457,500 2,202,542,5002,202,600,937.5 58,437.5 6 3135 1 32 29,523,160,000 2,201,840,0002,201,898,437.5 58,437.5 6 3134 1 33 29,523,862,500 2,201,137,5002,201,195,937.5 58,437.5 6 3133 1 34 29,524,565,000 2,200,435,0002,200,493,437.5 58,437.5 6 3132 1 35 29,525,267,500 2,199,732,5002,199,790,937.5 58,437.5 6 3131 1 36 29,525,970,000 2,199,030,0002,199,088,437.5 58,437.5 6 3130 1 37 29,526,672,500 2,198,327,5002,198,385,937.5 58,437.5 6 3129 1 38 29,527,375,000 2,197,625,0002,197,683,437.5 58,437.5 6 3128 1 39 29,528,077,500 2,196,922,5002,196,980,937.5 58,437.5 6 3127 1 40 29,528,780,000 2,196,220,0002,196,278,437.5 58,437.5 6 3126 1 41 29,529,482,500 2,195,517,5002,195,575,937.5 58,437.5 6 3125 1 42 29,530,185,000 2,194,815,0002,194,873,437.5 58,437.5 6 3124 1 43 29,530,887,500 2,194,112,5002,194,170,937.5 58,437.5 6 3123 1 44 29,531,590,000 2,193,410,0002,193,468,437.5 58,437.5 6 3122 1 45 29,532,292,500 2,192,707,5002,192,765,937.5 58,437.5 6 3121 1 46 29,532,995,000 2,192,005,0002,192,063,437.5 58,437.5 6 3120 1 47 29,533,697,500 2,191,302,5002,191,360,937.5 58,437.5 6 3119 1 48 29,534,400,000 2,190,600,0002,190,658,437.5 58,437.5 6 3118 1 49 29,535,102,500 2,189,897,5002,189,955,937.5 58,437.5 6 3117 1 50 29,535,805,000 2,189,195,0002,189,253,437.5 58,437.5 6 3116 1 51 29,536,507,500 2,188,492,5002,188,550,937.5 58,437.5 6 3115 1 52 29,537,210,000 2,187,790,0002,187,848,437.5 58,437.5 6 3114 1 53 29,537,912,500 2,187,087,5002,187,145,937.5 58,437.5 6 3113 1 54 29,538,615,000 2,186,385,0002,186,443,437.5 58,437.5 6 3112 1 55 29,539,317,500 2,185,682,5002,185,740,937.5 58,437.5 6 3111 1 56 29,540,020,000 2,184,980,0002,185,038,437.5 58,437.5 6 3110 1 57 29,540,722,500 2,184,277,5002,184,335,937.5 58,437.5 6 3109 1 58 29,541,425,000 2,183,575,0002,183,633,437.5 58,437.5 6 3108 1 59 29,542,127,500 2,182,872,5002,182,930,937.5 58,437.5 6 3107 1 60 29,542,830,000 2,182,170,0002,182,228,437.5 58,437.5 6 3106 1 61 29,543,532,500 2,181,467,5002,181,525,937.5 58,437.5 6 3105 1 62 29,544,235,000 2,180,765,0002,180,823,437.5 58,437.5 6 3104 1 63 29,544,937,500 2,180,062,5002,180,120,937.5 58,437.5 6 3103 1 64 29,545,640,000 2,179,360,0002,179,418,437.5 58,437.5 6 3102 1 65 29,546,342,500 2,178,657,5002,178,715,937.5 58,437.5 6 3101 1 66 29,547,045,000 2,177,955,0002,178,013,437.5 58,437.5 6 3100 1 67 29,547,747,500 2,177,252,5002,177,310,937.5 58,437.5 6 3099 1 68 29,548,450,000 2,176,550,0002,176,608,437.5 58,437.5 6 3098 1 69 29,549,152,500 2,175,847,5002,175,905,937.5 58,437.5 6 3097 1 70 29,549,855,000 2,175,145,0002,175,203,437.5 58,437.5 6 3096 1 71 29,550,557,500 2,174,442,5002,174,500,937.5 58,437.5 6 3095 1 72 29,551,260,000 2,173,740,0002,173,798,437.5 58,437.5 6 3094 1 73 29,551,962,500 2,173,037,5002,173,095,937.5 58,437.5 6 3093 1 74 29,552,665,000 2,172,335,0002,172,393,437.5 58,437.5 6 3092 1 75 29,553,367,500 2,171,632,5002,171,690,937.5 58,437.5 6 3091 1 76 29,554,070,000 2,170,930,0002,170,988,437.5 58,437.5 6 3090 1 77 29,554,772,500 2,170,227,5002,170,285,937.5 58,437.5 6 3089 1 78 29,555,475,000 2,169,525,0002,169,583,437.5 58,437.5 6 3088 1 79 29,556,177,500 2,168,822,5002,168,880,937.5 58,437.5 6 3087 1 80 29,556,880,000 2,168,120,0002,168,178,437.5 58,437.5 6 3086 1 81 29,557,582,500 2,167,417,5002,167,475,937.5 58,437.5 6 3085 1 82 29,558,285,000 2,166,715,0002,166,773,437.5 58,437.5 6 3084 1 83 29,558,987,500 2,166,012,5002,166,070,937.5 58,437.5 6 3083 1 84 29,559,690,000 2,165,310,0002,165,368,437.5 58,437.5 6 3082 1 85 29,560,392,500 2,164,607,5002,164,665,937.5 58,437.5 6 3081 1 86 29,561,095,000 2,163,905,0002,163,963,437.5 58,437.5 6 3080 1 87 29,561,797,500 2,163,202,5002,163,260,937.5 58,437.5 6 3079 1 88 29,562,500,000 2,162,500,0002,162,558,437.5 58,437.5 6 3078 1 89 29,563,202,500 2,161,797,5002,161,855,937.5 58,437.5 6 3077 1 90 29,563,905,000 2,161,095,0002,161,153,437.5 58,437.5 6 3076 1 91 29,564,607,500 2,160,392,5002,160,450,937.5 58,437.5 6 3075 1 92 29,565,310,000 2,159,690,0002,159,748,437.5 58,437.5 6 3074 1 93 29,566,012,500 2,158,987,5002,159,045,937.5 58,437.5 6 3073 1 94 29,566,715,000 2,158,285,0002,158,343,437.5 58,437.5 6 3072 1 95 29,567,417,500 2,157,582,5002,157,640,937.5 58,437.5 6 3071 1 96 29,568,120,000 2,156,880,0002,156,938,437.5 58,437.5 6 3070 1 97 29,568,822,500 2,156,177,5002,156,235,937.5 58,437.5 6 3069 1 98 29,569,525,000 2,155,475,0002,155,533,437.5 58,437.5 6 3068 1 99 29,570,227,500 2,154,772,5002,154,830,937.5 58,437.5 6 3067 1 100 29,570,930,000 2,154,070,0002,154,128,437.5 58,437.5 6 3066 1 101 29,571,632,500 2,153,367,5002,153,425,937.5 58,437.5 6 3065 1 102 29,572,335,000 2,152,665,0002,152,723,437.5 58,437.5 6 3064 1 103 29,573,037,500 2,151,962,5002,152,020,937.5 58,437.5 6 3063 1 104 29,573,740,000 2,151,260,0002,151,318,437.5 58,437.5 6 3062 1 105 29,574,442,500 2,150,557,5002,150,615,937.5 58,437.5 6 3061 1 106 29,575,145,000 2,149,855,0002,149,913,437.5 58,437.5 6 3060 1 107 29,575,847,500 2,149,152,5002,149,210,937.5 58,437.5 6 3059 1 108 29,576,550,000 2,148,450,0002,148,508,437.5 58,437.5 6 3058 1 109 29,577,252,500 2,147,747,5002,147,805,937.5 58,437.5 6 3057 1 110 29,577,955,000 2,147,045,0002,147,103,437.5 58,437.5 6 3056 1 111 29,578,657,500 2,146,342,5002,146,400,937.5 58,437.5 6 3055 1 112 29,579,360,000 2,145,640,0002,145,698,437.5 58,437.5 6 3054 1 113 29,580,062,500 2,144,937,5002,144,995,937.5 58,437.5 6 3053 1 114 29,580,765,000 2,144,235,0002,144,293,437.5 58,437.5 6 3052 1 115 29,581,467,500 2,143,532,5002,143,590,937.5 58,437.5 6 3051 1 116 29,582,170,000 2,142,830,0002,142,888,437.5 58,437.5 6 3050 1 117 29,582,872,500 2,142,127,5002,142,185,937.5 58,437.5 6 3049 1 118 29,583,575,000 2,141,425,0002,141,483,437.5 58,437.5 6 3048 1 119 29,584,277,500 2,140,722,5002,140,780,937.5 58,437.5 6 3047 1 120 29,584,980,000 2,140,020,0002,140,078,437.5 58,437.5 6 3046 1 121 29,585,682,500 2,139,317,5002,139,375,937.5 58,437.5 6 3045 1 122 29,586,385,000 2,138,615,0002,138,673,437.5 58,437.5 6 3044 1 123 29,587,087,500 2,137,912,5002,137,970,937.5 58,437.5 6 3043 1 124 29,587,790,000 2,137,210,0002,137,268,437.5 58,437.5 6 3042 1 125 29,588,492,500 2,136,507,5002,136,565,937.5 58,437.5 6 3041 1 126 29,589,195,000 2,135,805,0002,135,863,437.5 58,437.5 6 3040 1 127 29,589,897,500 2,135,102,5002,135,160,937.5 58,437.5 6 3039 1 128 29,590,600,000 2,134,400,0002,134,458,437.5 58,437.5 6 3038 1 129 29,591,302,500 2,133,697,5002,133,755,937.5 58,437.5 6 3037 1 130 29,592,005,000 2,132,995,0002,133,053,437.5 58,437.5 6 3036 1 131 29,592,707,500 2,132,292,5002,132,350,937.5 58,437.5 6 3035 1 132 29,593,410,000 2,131,590,0002,131,648,437.5 58,437.5 6 3034 1 133 29,594,112,500 2,130,887,5002,130,945,937.5 58,437.5 6 3033 1 134 29,594,815,000 2,130,185,0002,130,243,437.5 58,437.5 6 3032 1 135 29,595,517,500 2,129,482,5002,129,540,937.5 58,437.5 6 3031 1 136 29,596,220,000 2,128,780,0002,128,838,437.5 58,437.5 6 3030 1 137 29,596,922,500 2,128,077,5002,128,135,937.5 58,437.5 6 3029 1 138 29,597,625,000 2,127,375,0002,127,433,437.5 58,437.5 6 3028 1 139 29,598,327,500 2,126,672,5002,126,730,937.5 58,437.5 6 3027 1 140 29,599,030,000 2,125,970,0002,126,028,437.5 58,437.5 6 3026 1 141 29,599,732,500 2,125,267,5002,125,325,937.5 58,437.5 6 3025 1 142 29,600,435,000 2,124,565,0002,124,623,437.5 58,437.5 6 3024 1 143 29,601,137,500 2,123,862,5002,123,920,937.5 58,437.5 6 3023 1 144 29,601,840,000 2,123,160,0002,123,218,437.5 58,437.5 6 3022 1 145 29,602,542,500 2,122,457,5002,122,515,937.5 58,437.5 6 3021 1 146 29,603,245,000 2,121,755,0002,121,813,437.5 58,437.5 6 3020 1 147 29,603,947,500 2,121,052,5002,121,110,937.5 58,437.5 6 3019 1 148 29,604,650,000 2,120,350,0002,120,408,437.5 58,437.5 6 3018 1 149 29,605,352,500 2,119,647,5002,119,705,937.5 58,437.5 6 3017 1 150 29,606,055,000 2,118,945,0002,119,003,437.5 58,437.5 6 3016 1 151 29,606,757,500 2,118,242,5002,118,300,937.5 58,437.5 6 3015 1 152 29,607,460,000 2,117,540,0002,117,598,437.5 58,437.5 6 3014 1 153 29,608,162,500 2,116,837,5002,116,895,937.5 58,437.5 6 3013 1 154 29,608,865,000 2,116,135,0002,116,193,437.5 58,437.5 6 3012 1 155 29,609,567,500 2,115,432,5002,115,490,937.5 58,437.5 6 3011 1 156 29,610,270,000 2,114,730,0002,114,788,437.5 58,437.5 6 3010 1 157 29,610,972,500 2,114,027,5002,114,085,937.5 58,437.5 6 3009 1 158 29,611,675,000 2,113,325,0002,113,383,437.5 58,437.5 6 3008 1 159 29,612,377,500 2,112,622,5002,112,680,937.5 58,437.5 6 3007 1 160 29,613,080,000 2,111,920,0002,111,978,437.5 58,437.5 6 3006 1 161 29,613,782,500 2,111,217,5002,111,275,937.5 58,437.5 6 3005 1 162 29,614,485,000 2,110,515,0002,110,573,437.5 58,437.5 6 3004 1 163 29,615,187,500 2,109,812,5002,109,870,937.5 58,437.5 6 3003 1 164 29,615,890,000 2,109,110,0002,109,168,437.5 58,437.5 6 3002 1 165 29,616,592,500 2,108,407,5002,108,465,937.5 58,437.5 6 3001 1 166 29,617,295,000 2,107,705,0002,107,763,437.5 58,437.5 6 3000 1 167 29,617,997,500 2,107,002,5002,107,060,937.5 58,437.5 6 2999 1 168 29,618,700,000 2,106,300,0002,106,358,437.5 58,437.5 6 2998 1 169 29,619,402,500 2,105,597,5002,105,655,937.5 58,437.5 6 2997 1 170 29,620,105,000 2,104,895,0002,104,953,437.5 58,437.5 6 2996 1 171 29,620,807,500 2,104,192,5002,104,250,937.5 58,437.5 6 2995 1 172 29,621,510,000 2,103,490,0002,103,548,437.5 58,437.5 6 2994 1 173 29,622,212,500 2,102,787,5002,102,845,937.5 58,437.5 6 2993 1 174 29,622,915,000 2,102,085,0002,102,143,437.5 58,437.5 6 2992 1 175 29,623,617,500 2,101,382,5002,101,440,937.5 58,437.5 6 2991

TABLE 3 Tuning Commands for Class A - Band 2 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 2 1 29,626,382,500 2,098,617,5002,098,630,937.5 13,437.5 6 2987 2 2 29,627,085,000 2,097,915,0002,097,928,437.5 13,437.5 6 2986 2 3 29,627,787,500 2,097,212,5002,097,225,937.5 13,437.5 6 2985 2 4 29,628,490,000 2,096,510,0002,096,523,437.5 13,437.5 6 2984 2 5 29,629,192,500 2,095,807,5002,095,820,937.5 13,437.5 6 2983 2 6 29,629,895,000 2,095,105,0002,095,118,437.5 13,437.5 6 2982 2 7 29,630,597,500 2,094,402,5002,094,415,937.5 13,437.5 6 2981 2 8 29,631,300,000 2,093,700,0002,093,713,437.5 13,437.5 6 2980 2 9 29,632,002,500 2,092,997,5002,093,010,937.5 13,437.5 6 2979 2 10 29,632,705,000 2,092,295,0002,092,308,437.5 13,437.5 6 2978 2 11 29,633,407,500 2,091,592,5002,091,605,937.5 13,437.5 6 2977 2 12 29,634,110,000 2,090,890,0002,090,903,437.5 13,437.5 6 2976 2 13 29,634,812,500 2,090,187,5002,090,200,937.5 13,437.5 6 2975 2 14 29,635,515,000 2,089,485,0002,089,498,437.5 13,437.5 6 2974 2 15 29,636,217,500 2,088,782,5002,088,795,937.5 13,437.5 6 2973 2 16 29,636,920,000 2,088,080,0002,088,093,437.5 13,437.5 6 2972 2 17 29,637,622,500 2,087,377,5002,087,390,937.5 13,437.5 6 2971 2 18 29,638,325,000 2,086,675,0002,086,688,437.5 13,437.5 6 2970 2 19 29,639,027,500 2,085,972,5002,085,985,937.5 13,437.5 6 2969 2 20 29,639,730,000 2,085,270,0002,085,283,437.5 13,437.5 6 2968 2 21 29,640,432,500 2,084,567,5002,084,580,937.5 13,437.5 6 2967 2 22 29,641,135,000 2,083,865,0002,083,878,437.5 13,437.5 6 2966 2 23 29,641,837,500 2,083,162,5002,083,175,937.5 13,437.5 6 2965 2 24 29,642,540,000 2,082,460,0002,082,473,437.5 13,437.5 6 2964 2 25 29,643,242,500 2,081,757,5002,081,770,937.5 13,437.5 6 2963 2 26 29,643,945,000 2,081,055,0002,081,068,437.5 13,437.5 6 2962 2 27 29,644,647,500 2,080,352,5002,080,365,937.5 13,437.5 6 2961 2 28 29,645,350,000 2,079,650,0002,079,663,437.5 13,437.5 6 2960 2 29 29,646,052,500 2,078,947,5002,078,960,937.5 13,437.5 6 2959 2 30 29,646,755,000 2,078,245,0002,078,258,437.5 13,437.5 6 2958 2 31 29,647,457,500 2,077,542,5002,077,555,937.5 13,437.5 6 2957 2 32 29,648,160,000 2,076,840,0002,076,853,437.5 13,437.5 6 2956 2 33 29,648,862,500 2,076,137,5002,076,150,937.5 13,437.5 6 2955 2 34 29,649,565,000 2,075,435,0002,075,448,437.5 13,437.5 6 2954 2 35 29,650,267,500 2,074,732,5002,074,745,937.5 13,437.5 6 2953 2 36 29,650,970,000 2,074,030,0002,074,043,437.5 13,437.5 6 2952 2 37 29,651,672,500 2,073,327,5002,073,340,937.5 13,437.5 6 2951 2 38 29,652,375,000 2,072,625,0002,072,638,437.5 13,437.5 6 2950 2 39 29,653,077,500 2,071,922,5002,071,935,937.5 13,437.5 6 2949 2 40 29,653,780,000 2,071,220,0002,071,233,437.5 13,437.5 6 2948 2 41 29,654,482,500 2,070,517,5002,070,530,937.5 13,437.5 6 2947 2 42 29,655,185,000 2,069,815,0002,069,828,437.5 13,437.5 6 2946 2 43 29,655,887,500 2,069,112,5002,069,125,937.5 13,437.5 6 2945 2 44 29,656,590,000 2,068,410,0002,068,423,437.5 13,437.5 6 2944 2 45 29,657,292,500 2,067,707,5002,067,720,937.5 13,437.5 6 2943 2 46 29,657,995,000 2,067,005,0002,067,018,437.5 13,437.5 6 2942 2 47 29,658,697,500 2,066,302,5002,066,315,937.5 13,437.5 6 2941 2 48 29,659,400,000 2,065,600,0002,065,613,437.5 13,437.5 6 2940 2 49 29,660,102,500 2,064,897,5002,064,910,937.5 13,437.5 6 2939 2 50 29,660,805,000 2,064,195,0002,064,208,437.5 13,437.5 6 2938 2 51 29,661,507,500 2,063,492,5002,063,505,937.5 13,437.5 6 2937 2 52 29,662,210,000 2,062,790,0002,062,803,437.5 13,437.5 6 2936 2 53 29,662,912,500 2,062,087,5002,062,100,937.5 13,437.5 6 2935 2 54 29,663,615,000 2,061,385,0002,061,398,437.5 13,437.5 6 2934 2 55 29,664,317,500 2,060,682,5002,060,695,937.5 13,437.5 6 2933 2 56 29,665,020,000 2,059,980,0002,059,993,437.5 13,437.5 6 2932 2 57 29,665,722,500 2,059,277,5002,059,290,937.5 13,437.5 6 2931 2 58 29,666,425,000 2,058,575,0002,058,588,437.5 13,437.5 6 2930 2 59 29,667,127,500 2,057,872,5002,057,885,937.5 13,437.5 6 2929 2 60 29,667,830,000 2,057,170,0002,057,183,437.5 13,437.5 6 2928 2 61 29,668,532,500 2,056,467,5002,056,480,937.5 13,437.5 6 2927 2 62 29,669,235,000 2,055,765,0002,055,778,437.5 13,437.5 6 2926 2 63 29,669,937,500 2,055,062,5002,055,075,937.5 13,437.5 6 2925 2 64 29,670,640,000 2,054,360,0002,054,373,437.5 13,437.5 6 2924 2 65 29,671,342,500 2,053,657,5002,053,670,937.5 13,437.5 6 2923 2 66 29,672,045,000 2,052,955,0002,052,968,437.5 13,437.5 6 2922 2 67 29,672,747,500 2,052,252,5002,052,265,937.5 13,437.5 6 2921 2 68 29,673,450,000 2,051,550,0002,051,563,437.5 13,437.5 6 2920 2 69 29,674,152,500 2,050,847,5002,050,860,937.5 13,437.5 6 2919 2 70 29,674,855,000 2,050,145,0002,050,158,437.5 13,437.5 6 2918 2 71 29,675,557,500 2,049,442,5002,049,455,937.5 13,437.5 6 2917 2 72 29,676,260,000 2,048,740,0002,048,753,437.5 13,437.5 6 2916 2 73 29,676,962,500 2,048,037,5002,048,050,937.5 13,437.5 6 2915 2 74 29,677,665,000 2,047,335,0002,047,348,437.5 13,437.5 6 2914 2 75 29,678,367,500 2,046,632,5002,046,645,937.5 13,437.5 6 2913 2 76 29,679,070,000 2,045,930,0002,045,943,437.5 13,437.5 6 2912 2 77 29,679,772,500 2,045,227,5002,045,240,937.5 13,437.5 6 2911 2 78 29,680,475,000 2,044,525,0002,044,538,437.5 13,437.5 6 2910 2 79 29,681,177,500 2,043,822,5002,043,835,937.5 13,437.5 6 2909 2 80 29,681,880,000 2,043,120,0002,043,133,437.5 13,437.5 6 2908 2 81 29,682,582,500 2,042,417,5002,042,430,937.5 13,437.5 6 2907 2 82 29,683,285,000 2,041,715,0002,041,728,437.5 13,437.5 6 2906 2 83 29,683,987,500 2,041,012,5002,041,025,937.5 13,437.5 6 2905 2 84 29,684,690,000 2,040,310,0002,040,323,437.5 13,437.5 6 2904 2 85 29,685,392,500 2,039,607,5002,039,620,937.5 13,437.5 6 2903 2 86 29,686,095,000 2,038,905,0002,038,918,437.5 13,437.5 6 2902 2 87 29,686,797,500 2,038,202,5002,038,215,937.5 13,437.5 6 2901 2 88 29,687,500,000 2,037,500,0002,037,513,437.5 13,437.5 6 2900 2 89 29,688,202,500 2,036,797,5002,036,810,937.5 13,437.5 6 2899 2 90 29,688,905,000 2,036,095,0002,036,108,437.5 13,437.5 6 2898 2 91 29,689,607,500 2,035,392,5002,035,405,937.5 13,437.5 6 2897 2 92 29,690,310,000 2,034,690,0002,034,703,437.5 13,437.5 6 2896 2 93 29,691,012,500 2,033,987,5002,034,000,937.5 13,437.5 6 2895 2 94 29,691,715,000 2,033,285,0002,033,298,437.5 13,437.5 6 2894 2 95 29,692,417,500 2,032,582,5002,032,595,937.5 13,437.5 6 2893 2 96 29,693,120,000 2,031,880,0002,031,893,437.5 13,437.5 6 2892 2 97 29,693,822,500 2,031,177,5002,031,190,937.5 13,437.5 6 2891 2 98 29,694,525,000 2,030,475,0002,030,488,437.5 13,437.5 6 2890 2 99 29,695,227,500 2,029,772,5002,029,785,937.5 13,437.5 6 2889 2 100 29,695,930,000 2,029,070,0002,029,083,437.5 13,437.5 6 2888 2 101 29,696,632,500 2,028,367,5002,028,380,937.5 13,437.5 6 2887 2 102 29,697,335,000 2,027,665,0002,027,678,437.5 13,437.5 6 2886 2 103 29,698,037,500 2,026,962,5002,026,975,937.5 13,437.5 6 2885 2 104 29,698,740,000 2,026,260,0002,026,273,437.5 13,437.5 6 2884 2 105 29,699,442,500 2,025,557,5002,025,570,937.5 13,437.5 6 2883 2 106 29,700,145,000 2,024,855,0002,024,868,437.5 13,437.5 6 2882 2 107 29,700,847,500 2,024,152,5002,024,165,937.5 13,437.5 6 2881 2 108 29,701,550,000 2,023,450,0002,023,463,437.5 13,437.5 6 2880 2 109 29,702,252,500 2,022,747,5002,022,760,937.5 13,437.5 6 2879 2 110 29,702,955,000 2,022,045,0002,022,058,437.5 13,437.5 6 2878 2 111 29,703,657,500 2,021,342,5002,021,355,937.5 13,437.5 6 2877 2 112 29,704,360,000 2,020,640,0002,020,653,437.5 13,437.5 6 2876 2 113 29,705,062,500 2,019,937,5002,019,950,937.5 13,437.5 6 2875 2 114 29,705,765,000 2,019,235,0002,019,248,437.5 13,437.5 6 2874 2 115 29,706,467,500 2,018,532,5002,018,545,937.5 13,437.5 6 2873 2 116 29,707,170,000 2,017,830,0002,017,843,437.5 13,437.5 6 2872 2 117 29,707,872,500 2,017,127,5002,017,140,937.5 13,437.5 6 2871 2 118 29,708,575,000 2,016,425,0002,016,438,437.5 13,437.5 6 2870 2 119 29,709,277,500 2,015,722,5002,015,735,937.5 13,437.5 6 2869 2 120 29,709,980,000 2,015,020,0002,015,033,437.5 13,437.5 6 2868 2 121 29,710,682,500 2,014,317,5002,014,330,937.5 13,437.5 6 2867 2 122 29,711,385,000 2,013,615,0002,013,628,437.5 13,437.5 6 2866 2 123 29,712,087,500 2,012,912,5002,012,925,937.5 13,437.5 6 2865 2 124 29,712,790,000 2,012,210,0002,012,223,437.5 13,437.5 6 2864 2 125 29,713,492,500 2,011,507,5002,011,520,937.5 13,437.5 6 2863 2 126 29,714,195,000 2,010,805,0002,010,818,437.5 13,437.5 6 2862 2 127 29,714,897,500 2,010,102,5002,010,115,937.5 13,437.5 6 2861 2 128 29,715,600,000 2,009,400,0002,009,413,437.5 13,437.5 6 2860 2 129 29,716,302,500 2,008,697,5002,008,710,937.5 13,437.5 6 2859 2 130 29,717,005,000 2,007,995,0002,008,008,437.5 13,437.5 6 2858 2 131 29,717,707,500 2,007,292,5002,007,305,937.5 13,437.5 6 2857 2 132 29,718,410,000 2,006,590,0002,006,603,437.5 13,437.5 6 2856 2 133 29,719,112,500 2,005,887,5002,005,900,937.5 13,437.5 6 2855 2 134 29,719,815,000 2,005,185,0002,005,198,437.5 13,437.5 6 2854 2 135 29,720,517,500 2,004,482,5002,004,495,937.5 13,437.5 6 2853 2 136 29,721,220,000 2,003,780,0002,003,793,437.5 13,437.5 6 2852 2 137 29,721,922,500 2,003,077,5002,003,090,937.5 13,437.5 6 2851 2 138 29,722,625,000 2,002,375,0002,002,388,437.5 13,437.5 6 2850 2 139 29,723,327,500 2,001,672,5002,001,685,937.5 13,437.5 6 2849 2 140 29,724,030,000 2,000,970,0002,000,983,437.5 13,437.5 6 2848 2 141 29,724,732,500 2,000,267,5002,000,280,937.5 13,437.5 6 2847 2 142 29,725,435,000 1,999,565,0001,999,578,437.5 13,437.5 6 2846 2 143 29,726,137,500 1,998,862,5001,998,875,937.5 13,437.5 6 2845 2 144 29,726,840,000 1,998,160,0001,998,173,437.5 13,437.5 6 2844 2 145 29,727,542,500 1,997,457,5001,997,470,937.5 13,437.5 6 2843 2 146 29,728,245,000 1,996,755,0001,996,768,437.5 13,437.5 6 2842 2 147 29,728,947,500 1,996,052,5001,996,065,937.5 13,437.5 6 2841 2 148 29,729,650,000 1,995,350,0001,995,363,437.5 13,437.5 6 2840 2 149 29,730,352,500 1,994,647,5001,994,660,937.5 13,437.5 6 2839 2 150 29,731,055,000 1,993,945,0001,993,958,437.5 13,437.5 6 2838 2 151 29,731,757,500 1,993,242,5001,993,255,937.5 13,437.5 6 2837 2 152 29,732,460,000 1,992,540,0001,992,553,437.5 13,437.5 6 2836 2 153 29,733,162,500 1,991,837,5001,991,850,937.5 13,437.5 6 2835 2 154 29,733,865,000 1,991,135,0001,991,148,437.5 13,437.5 6 2834 2 155 29,734,567,500 1,990,432,5001,990,445,937.5 13,437.5 6 2833 2 156 29,735,270,000 1,989,730,0001,989,743,437.5 13,437.5 6 2832 2 157 29,735,972,500 1,989,027,5001,989,040,937.5 13,437.5 6 2831 2 158 29,736,675,000 1,988,325,0001,988,338,437.5 13,437.5 6 2830 2 159 29,737,377,500 1,987,622,5001,987,635,937.5 13,437.5 6 2829 2 160 29,738,080,000 1,986,920,0001,986,933,437.5 13,437.5 6 2828 2 161 29,738,782,500 1,986,217,5001,986,230,937.5 13,437.5 6 2827 2 162 29,739,485,000 1,985,515,0001,985,528,437.5 13,437.5 6 2826 2 163 29,740,187,500 1,984,812,5001,984,825,937.5 13,437.5 6 2825 2 164 29,740,890,000 1,984,110,0001,984,123,437.5 13,437.5 6 2824 2 165 29,741,592,500 1,983,407,5001,983,420,937.5 13,437.5 6 2823 2 166 29,742,295,000 1,982,705,0001,982,718,437.5 13,437.5 6 2822 2 167 29,742,997,500 1,982,002,5001,982,015,937.5 13,437.5 6 2821 2 168 29,743,700,000 1,981,300,0001,981,313,437.5 13,437.5 6 2820 2 169 29,744,402,500 1,980,597,5001,980,610,937.5 13,437.5 6 2819 2 170 29,745,105,000 1,979,895,0001,979,908,437.5 13,437.5 6 2818 2 171 29,745,807,500 1,979,192,5001,979,205,937.5 13,437.5 6 2817 2 172 29,746,510,000 1,978,490,0001,978,503,437.5 13,437.5 6 2816 2 173 29,747,212,500 1,977,787,5001,977,800,937.5 13,437.5 6 2815 2 174 29,747,915,000 1,977,085,0001,977,098,437.5 13,437.5 6 2814 2 175 29,748,617,500 1,976,382,5001,976,395,937.5 13,437.5 6 2813

TABLE 4 Tuning Commands for Class A - Band 3 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 3 1 29,751,382,500 1,973,617,5001,973,673,750.0 56,250.0 8 2809 3 2 29,752,085,000 1,972,915,0001,972,971,250.0 56,250.0 8 2808 3 3 29,752,787,500 1,972,212,5001,972,268,750.0 56,250.0 8 2807 3 4 29,753,490,000 1,971,510,0001,971,566,250.0 56,250.0 8 2806 3 5 29,754,192,500 1,970,807,5001,970,863,750.0 56,250.0 8 2805 3 6 29,754,895,000 1,970,105,0001,970,161,250.0 56,250.0 8 2804 3 7 29,755,597,500 1,969,402,5001,969,458,750.0 56,250.0 8 2803 3 8 29,756,300,000 1,968,700,0001,968,756,250.0 56,250.0 8 2802 3 9 29,757,002,500 1,967,997,5001,968,053,750.0 56,250.0 8 2801 3 10 29,757,705,000 1,967,295,0001,967,351,250.0 56,250.0 8 2800 3 11 29,758,407,500 1,966,592,5001,966,648,750.0 56,250.0 8 2799 3 12 29,759,110,000 1,965,890,0001,965,946,250.0 56,250.0 8 2798 3 13 29,759,812,500 1,965,187,5001,965,243,750.0 56,250.0 8 2797 3 14 29,760,515,000 1,964,485,0001,964,541,250.0 56,250.0 8 2796 3 15 29,761,217,500 1,963,782,5001,963,838,750.0 56,250.0 8 2795 3 16 29,761,920,000 1,963,080,0001,963,136,250.0 56,250.0 8 2794 3 17 29,762,622,500 1,962,377,5001,962,433,750.0 56,250.0 8 2793 3 18 29,763,325,000 1,961,675,0001,961,731,250.0 56,250.0 8 2792 3 19 29,764,027,500 1,960,972,5001,961,028,750.0 56,250.0 8 2791 3 20 29,764,730,000 1,960,270,0001,960,326,250.0 56,250.0 8 2790 3 21 29,765,432,500 1,959,567,5001,959,623,750.0 56,250.0 8 2789 3 22 29,766,135,000 1,958,865,0001,958,921,250.0 56,250.0 8 2788 3 23 29,766,837,500 1,958,162,5001,958,218,750.0 56,250.0 8 2787 3 24 29,767,540,000 1,957,460,0001,957,516,250.0 56,250.0 8 2786 3 25 29,768,242,500 1,956,757,5001,956,813,750.0 56,250.0 8 2785 3 26 29,768,945,000 1,956,055,0001,956,111,250.0 56,250.0 8 2784 3 27 29,769,647,500 1,955,352,5001,955,408,750.0 56,250.0 8 2783 3 28 29,770,350,000 1,954,650,0001,954,706,250.0 56,250.0 8 2782 3 29 29,771,052,500 1,953,947,5001,954,003,750.0 56,250.0 8 2781 3 30 29,771,755,000 1,953,245,0001,953,301,250.0 56,250.0 8 2780 3 31 29,772,457,500 1,952,542,5001,952,598,750.0 56,250.0 8 2779 3 32 29,773,160,000 1,951,840,0001,951,896,250.0 56,250.0 8 2778 3 33 29,773,862,500 1,951,137,5001,951,193,750.0 56,250.0 8 2777 3 34 29,774,565,000 1,950,435,0001,950,491,250.0 56,250.0 8 2776 3 35 29,775,267,500 1,949,732,5001,949,788,750.0 56,250.0 8 2775 3 36 29,775,970,000 1,949,030,0001,949,086,250.0 56,250.0 8 2774 3 37 29,776,672,500 1,948,327,5001,948,383,750.0 56,250.0 8 2773 3 38 29,777,375,000 1,947,625,0001,947,681,250.0 56,250.0 8 2772 3 39 29,778,077,500 1,946,922,5001,946,978,750.0 56,250.0 8 2771 3 40 29,778,780,000 1,946,220,0001,946,276,250.0 56,250.0 8 2770 3 41 29,779,482,500 1,945,517,5001,945,573,750.0 56,250.0 8 2769 3 42 29,780,185,000 1,944,815,0001,944,871,250.0 56,250.0 8 2768 3 43 29,780,887,500 1,944,112,5001,944,168,750.0 56,250.0 8 2767 3 44 29,781,590,000 1,943,410,0001,943,466,250.0 56,250.0 8 2766 3 45 29,782,292,500 1,942,707,5001,942,763,750.0 56,250.0 8 2765 3 46 29,782,995,000 1,942,005,0001,942,061,250.0 56,250.0 8 2764 3 47 29,783,697,500 1,941,302,5001,941,358,750.0 56,250.0 8 2763 3 48 29,784,400,000 1,940,600,0001,940,656,250.0 56,250.0 8 2762 3 49 29,785,102,500 1,939,897,5001,939,953,750.0 56,250.0 8 2761 3 50 29,785,805,000 1,939,195,0001,939,251,250.0 56,250.0 8 2760 3 51 29,786,507,500 1,938,492,5001,938,548,750.0 56,250.0 8 2759 3 52 29,787,210,000 1,937,790,0001,937,846,250.0 56,250.0 8 2758 3 53 29,787,912,500 1,937,087,5001,937,143,750.0 56,250.0 8 2757 3 54 29,788,615,000 1,936,385,0001,936,441,250.0 56,250.0 8 2756 3 55 29,789,317,500 1,935,682,5001,935,738,750.0 56,250.0 8 2755 3 56 29,790,020,000 1,934,980,0001,935,036,250.0 56,250.0 8 2754 3 57 29,790,722,500 1,934,277,5001,934,333,750.0 56,250.0 8 2753 3 58 29,791,425,000 1,933,575,0001,933,631,250.0 56,250.0 8 2752 3 59 29,792,127,500 1,932,872,5001,932,928,750.0 56,250.0 8 2751 3 60 29,792,830,000 1,932,170,0001,932,226,250.0 56,250.0 8 2750 3 61 29,793,532,500 1,931,467,5001,931,523,750.0 56,250.0 8 2749 3 62 29,794,235,000 1,930,765,0001,930,821,250.0 56,250.0 8 2748 3 63 29,794,937,500 1,930,062,5001,930,118,750.0 56,250.0 8 2747 3 64 29,795,640,000 1,929,360,0001,929,416,250.0 56,250.0 8 2746 3 65 29,796,342,500 1,928,657,5001,928,713,750.0 56,250.0 8 2745 3 66 29,797,045,000 1,927,955,0001,928,011,250.0 56,250.0 8 2744 3 67 29,797,747,500 1,927,252,5001,927,308,750.0 56,250.0 8 2743 3 68 29,798,450,000 1,926,550,0001,926,606,250.0 56,250.0 8 2742 3 69 29,799,152,500 1,925,847,5001,925,903,750.0 56,250.0 8 2741 3 70 29,799,855,000 1,925,145,0001,925,201,250.0 56,250.0 8 2740 3 71 29,800,557,500 1,924,442,5001,924,498,750.0 56,250.0 8 2739 3 72 29,801,260,000 1,923,740,0001,923,796,250.0 56,250.0 8 2738 3 73 29,801,962,500 1,923,037,5001,923,093,750.0 56,250.0 8 2737 3 74 29,802,665,000 1,922,335,0001,922,391,250.0 56,250.0 8 2736 3 75 29,803,367,500 1,921,632,5001,921,688,750.0 56,250.0 8 2735 3 76 29,804,070,000 1,920,930,0001,920,986,250.0 56,250.0 8 2734 3 77 29,804,772,500 1,920,227,5001,920,283,750.0 56,250.0 8 2733 3 78 29,805,475,000 1,919,525,0001,919,581,250.0 56,250.0 8 2732 3 79 29,806,177,500 1,918,822,5001,918,878,750.0 56,250.0 8 2731 3 80 29,806,880,000 1,918,120,0001,918,176,250.0 56,250.0 8 2730 3 81 29,807,582,500 1,917,417,5001,917,473,750.0 56,250.0 8 2729 3 82 29,808,285,000 1,916,715,0001,916,771,250.0 56,250.0 8 2728 3 83 29,808,987,500 1,916,012,5001,916,068,750.0 56,250.0 8 2727 3 84 29,809,690,000 1,915,310,0001,915,366,250.0 56,250.0 8 2726 3 85 29,810,392,500 1,914,607,5001,914,663,750.0 56,250.0 8 2725 3 86 29,811,095,000 1,913,905,0001,913,961,250.0 56,250.0 8 2724 3 87 29,811,797,500 1,913,202,5001,913,258,750.0 56,250.0 8 2723 3 88 29,812,500,000 1,912,500,0001,912,556,250.0 56,250.0 8 2722 3 89 29,813,202,500 1,911,797,5001,911,853,750.0 56,250.0 8 2721 3 90 29,813,905,000 1,911,095,0001,911,151,250.0 56,250.0 8 2720 3 91 29,814,607,500 1,910,392,5001,910,448,750.0 56,250.0 8 2719 3 92 29,815,310,000 1,909,690,0001,909,746,250.0 56,250.0 8 2718 3 93 29,816,012,500 1,908,987,5001,909,043,750.0 56,250.0 8 2717 3 94 29,816,715,000 1,908,285,0001,908,341,250.0 56,250.0 8 2716 3 95 29,817,417,500 1,907,582,5001,907,638,750.0 56,250.0 8 2715 3 96 29,818,120,000 1,906,880,0001,906,936,250.0 56,250.0 8 2714 3 97 29,818,822,500 1,906,177,5001,906,233,750.0 56,250.0 8 2713 3 98 29,819,525,000 1,905,475,0001,905,531,250.0 56,250.0 8 2712 3 99 29,820,227,500 1,904,772,5001,904,828,750.0 56,250.0 8 2711 3 100 29,820,930,000 1,904,070,0001,904,126,250.0 56,250.0 8 2710 3 101 29,821,632,500 1,903,367,5001,903,423,750.0 56,250.0 8 2709 3 102 29,822,335,000 1,902,665,0001,902,721,250.0 56,250.0 8 2708 3 103 29,823,037,500 1,901,962,5001,902,018,750.0 56,250.0 8 2707 3 104 29,823,740,000 1,901,260,0001,901,316,250.0 56,250.0 8 2706 3 105 29,824,442,500 1,900,557,5001,900,613,750.0 56,250.0 8 2705 3 106 29,825,145,000 1,899,855,0001,899,911,250.0 56,250.0 8 2704 3 107 29,825,847,500 1,899,152,5001,899,208,750.0 56,250.0 8 2703 3 108 29,826,550,000 1,898,450,0001,898,506,250.0 56,250.0 8 2702 3 109 29,827,252,500 1,897,747,5001,897,803,750.0 56,250.0 8 2701 3 110 29,827,955,000 1,897,045,0001,897,101,250.0 56,250.0 8 2700 3 111 29,828,657,500 1,896,342,5001,896,398,750.0 56,250.0 8 2699 3 112 29,829,360,000 1,895,640,0001,895,696,250.0 56,250.0 8 2698 3 113 29,830,062,500 1,894,937,5001,894,993,750.0 56,250.0 8 2697 3 114 29,830,765,000 1,894,235,0001,894,291,250.0 56,250.0 8 2696 3 115 29,831,467,500 1,893,532,5001,893,588,750.0 56,250.0 8 2695 3 116 29,832,170,000 1,892,830,0001,892,886,250.0 56,250.0 8 2694 3 117 29,832,872,500 1,892,127,5001,892,183,750.0 56,250.0 8 2693 3 118 29,833,575,000 1,891,425,0001,891,481,250.0 56,250.0 8 2692 3 119 29,834,277,500 1,890,722,5001,890,778,750.0 56,250.0 8 2691 3 120 29,834,980,000 1,890,020,0001,890,076,250.0 56,250.0 8 2690 3 121 29,835,682,500 1,889,317,5001,889,373,750.0 56,250.0 8 2689 3 122 29,836,385,000 1,888,615,0001,888,671,250.0 56,250.0 8 2688 3 123 29,837,087,500 1,887,912,5001,887,968,750.0 56,250.0 8 2687 3 124 29,837,790,000 1,887,210,0001,887,266,250.0 56,250.0 8 2686 3 125 29,838,492,500 1,886,507,5001,886,563,750.0 56,250.0 8 2685 3 126 29,839,195,000 1,885,805,0001,885,861,250.0 56,250.0 8 2684 3 127 29,839,897,500 1,885,102,5001,885,158,750.0 56,250.0 8 2683 3 128 29,840,600,000 1,884,400,0001,884,456,250.0 56,250.0 8 2682 3 129 29,841,302,500 1,883,697,5001,883,753,750.0 56,250.0 8 2681 3 130 29,842,005,000 1,882,995,0001,883,051,250.0 56,250.0 8 2680 3 131 29,842,707,500 1,882,292,5001,882,348,750.0 56,250.0 8 2679 3 132 29,843,410,000 1,881,590,0001,881,646,250.0 56,250.0 8 2678 3 133 29,844,112,500 1,880,887,5001,880,943,750.0 56,250.0 8 2677 3 134 29,844,815,000 1,880,185,0001,880,241,250.0 56,250.0 8 2676 3 135 29,845,517,500 1,879,482,5001,879,538,750.0 56,250.0 8 2675 3 136 29,846,220,000 1,878,780,0001,878,836,250.0 56,250.0 8 2674 3 137 29,846,922,500 1,878,077,5001,878,133,750.0 56,250.0 8 2673 3 138 29,847,625,000 1,877,375,0001,877,431,250.0 56,250.0 8 2672 3 139 29,848,327,500 1,876,672,5001,876,728,750.0 56,250.0 8 2671 3 140 29,849,030,000 1,875,970,0001,876,026,250.0 56,250.0 8 2670 3 141 29,849,732,500 1,875,267,5001,875,323,750.0 56,250.0 8 2669 3 142 29,850,435,000 1,874,565,0001,874,621,250.0 56,250.0 8 2668 3 143 29,851,137,500 1,873,862,5001,873,918,750.0 56,250.0 8 2667 3 144 29,851,840,000 1,873,160,0001,873,216,250.0 56,250.0 8 2666 3 145 29,852,542,500 1,872,457,5001,872,513,750.0 56,250.0 8 2665 3 146 29,853,245,000 1,871,755,0001,871,811,250.0 56,250.0 8 2664 3 147 29,853,947,500 1,871,052,5001,871,108,750.0 56,250.0 8 2663 3 148 29,854,650,000 1,870,350,0001,870,406,250.0 56,250.0 8 2662 3 149 29,855,352,500 1,869,647,5001,869,703,750.0 56,250.0 8 2661 3 150 29,856,055,000 1,868,945,0001,869,001,250.0 56,250.0 8 2660 3 151 29,856,757,500 1,868,242,5001,868,298,750.0 56,250.0 8 2659 3 152 29,857,460,000 1,867,540,0001,867,596,250.0 56,250.0 8 2658 3 153 29,858,162,500 1,866,837,5001,866,893,750.0 56,250.0 8 2657 3 154 29,858,865,000 1,866,135,0001,866,191,250.0 56,250.0 8 2656 3 155 29,859,567,500 1,865,432,5001,865,488,750.0 56,250.0 8 2655 3 156 29,860,270,000 1,864,730,0001,864,786,250.0 56,250.0 8 2654 3 157 29,860,972,500 1,864,027,5001,864,083,750.0 56,250.0 8 2653 3 158 29,861,675,000 1,863,325,0001,863,381,250.0 56,250.0 8 2652 3 159 29,862,377,500 1,862,622,5001,862,678,750.0 56,250.0 8 2651 3 160 29,863,080,000 1,861,920,0001,861,976,250.0 56,250.0 8 2650 3 161 29,863,782,500 1,861,217,5001,861,273,750.0 56,250.0 8 2649 3 162 29,864,485,000 1,860,515,0001,860,571,250.0 56,250.0 8 2648 3 163 29,865,187,500 1,859,812,5001,859,868,750.0 56,250.0 8 2647 3 164 29,865,890,000 1,859,110,0001,859,166,250.0 56,250.0 8 2646 3 165 29,866,592,500 1,858,407,5001,858,463,750.0 56,250.0 8 2645 3 166 29,867,295,000 1,857,705,0001,857,761,250.0 56,250.0 8 2644 3 167 29,867,997,500 1,857,002,5001,857,058,750.0 56,250.0 8 2643 3 168 29,868,700,000 1,856,300,0001,856,356,250.0 56,250.0 8 2642 3 169 29,869,402,500 1,855,597,5001,855,653,750.0 56,250.0 8 2641 3 170 29,870,105,000 1,854,895,0001,854,951,250.0 56,250.0 8 2640 3 171 29,870,807,500 1,854,192,5001,854,248,750.0 56,250.0 8 2639 3 172 29,871,510,000 1,853,490,0001,853,546,250.0 56,250.0 8 2638 3 173 29,872,212,500 1,852,787,5001,852,843,750.0 56,250.0 8 2637 3 174 29,872,915,000 1,852,085,0001,852,141,250.0 56,250.0 8 2636 3 175 29,873,617,500 1,851,382,5001,851,438,750.0 56,250.0 8 2635

TABLE 5 Tuning Commands for Class A - Band 4 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 1 1 29,876,382,500 1,848,617,5001,848,628,750.0 11,250.0 8 2631 4 2 29,877,085,000 1,847,915,0001,847,926,250.0 11,250.0 8 2630 4 3 29,877,787,500 1,847,212,5001,847,223,750.0 11,250.0 8 2629 4 4 29,878,490,000 1,846,510,0001,846,521,250.0 11,250.0 8 2628 4 5 29,879,192,500 1,845,807,5001,845,818,750.0 11,250.0 8 2627 4 6 29,879,895,000 1,845,105,0001,845,116,250.0 11,250.0 8 2626 4 7 29,880,597,500 1,844,402,5001,844,413,750.0 11,250.0 8 2625 4 8 29,881,300,000 1,843,700,0001,843,711,250.0 11,250.0 8 2624 4 9 29,882,002,500 1,842,997,5001,843,008,750.0 11,250.0 8 2623 4 10 29,882,705,000 1,842,295,0001,842,306,250.0 11,250.0 8 2622 4 11 29,883,407,500 1,841,592,5001,841,603,750.0 11,250.0 8 2621 4 12 29,884,110,000 1,840,890,0001,840,901,250.0 11,250.0 8 2620 4 13 29,884,812,500 1,840,187,5001,840,198,750.0 11,250.0 8 2619 4 14 29,885,515,000 1,839,485,0001,839,496,250.0 11,250.0 8 2618 4 15 29,886,217,500 1,838,782,5001,838,793,750.0 11,250.0 8 2617 4 16 29,886,920,000 1,838,080,0001,838,091,250.0 11,250.0 8 2616 4 17 29,887,622,500 1,837,377,5001,837,388,750.0 11,250.0 8 2615 4 18 29,888,325,000 1,836,675,0001,836,686,250.0 11,250.0 8 2614 4 19 29,889,027,500 1,835,972,5001,835,983,750.0 11,250.0 8 2613 4 20 29,889,730,000 1,835,270,0001,835,281,250.0 11,250.0 8 2612 4 21 29,890,432,500 1,834,567,5001,834,578,750.0 11,250.0 8 2611 4 22 29,891,135,000 1,833,865,0001,833,876,250.0 11,250.0 8 2610 4 23 29,891,837,500 1,833,162,5001,833,173,750.0 11,250.0 8 2609 4 24 29,892,540,000 1,832,460,0001,832,471,250.0 11,250.0 8 2608 4 25 29,893,242,500 1,831,757,5001,831,768,750.0 11,250.0 8 2607 4 26 29,893,945,000 1,831,055,0001,831,066,250.0 11,250.0 8 2606 4 27 29,894,647,500 1,830,352,5001,830,363,750.0 11,250.0 8 2605 4 28 29,895,350,000 1,829,650,0001,829,661,250.0 11,250.0 8 2604 4 29 29,896,052,500 1,828,947,5001,828,958,750.0 11,250.0 8 2603 4 30 29,896,755,000 1,828,245,0001,828,256,250.0 11,250.0 8 2602 4 31 29,897,457,500 1,827,542,5001,827,553,750.0 11,250.0 8 2601 4 32 29,898,160,000 1,826,840,0001,826,851,250.0 11,250.0 8 2600 4 33 29,898,862,500 1,826,137,5001,826,148,750.0 11,250.0 8 2599 4 34 29,899,565,000 1,825,435,0001,825,446,250.0 11,250.0 8 2598 4 35 29,900,267,500 1,824,732,5001,824,743,750.0 11,250.0 8 2597 4 36 29,900,970,000 1,824,030,0001,824,041,250.0 11,250.0 8 2596 4 37 29,901,672,500 1,823,327,5001,823,338,750.0 11,250.0 8 2595 4 38 29,902,375,000 1,822,625,0001,822,636,250.0 11,250.0 8 2594 4 39 29,903,077,500 1,821,922,5001,821,933,750.0 11,250.0 8 2593 4 40 29,903,780,000 1,821,220,0001,821,231,250.0 11,250.0 8 2592 4 41 29,904,482,500 1,820,517,5001,820,528,750.0 11,250.0 8 2591 4 42 29,905,185,000 1,819,815,0001,819,826,250.0 11,250.0 8 2590 4 43 29,905,887,500 1,819,112,5001,819,123,750.0 11,250.0 8 2589 4 44 29,906,590,000 1,818,410,0001,818,421,250.0 11,250.0 8 2588 4 45 29,907,292,500 1,817,707,5001,817,718,750.0 11,250.0 8 2587 4 46 29,907,995,000 1,817,005,0001,817,016,250.0 11,250.0 8 2586 4 47 29,908,697,500 1,816,302,5001,816,313,750.0 11,250.0 8 2585 4 48 29,909,400,000 1,815,600,0001,815,611,250.0 11,250.0 8 2584 4 49 29,910,102,500 1,814,897,5001,814,908,750.0 11,250.0 8 2583 4 50 29,910,805,000 1,814,195,0001,814,206,250.0 11,250.0 8 2582 4 51 29,911,507,500 1,813,492,5001,813,503,750.0 11,250.0 8 2581 4 52 29,912,210,000 1,812,790,0001,812,801,250.0 11,250.0 8 2580 4 53 29,912,912,500 1,812,087,5001,812,098,750.0 11,250.0 8 2579 4 54 29,913,615,000 1,811,385,0001,811,396,250.0 11,250.0 8 2578 4 55 29,914,317,500 1,810,682,5001,810,693,750.0 11,250.0 8 2577 4 56 29,915,020,000 1,809,980,0001,809,991,250.0 11,250.0 8 2576 4 57 29,915,722,500 1,809,277,5001,809,288,750.0 11,250.0 8 2575 4 58 29,916,425,000 1,808,575,0001,808,586,250.0 11,250.0 8 2574 4 59 29,917,127,500 1,807,872,5001,807,883,750.0 11,250.0 8 2573 4 60 29,917,830,000 1,807,170,0001,807,181,250.0 11,250.0 8 2572 4 61 29,918,532,500 1,806,467,5001,806,478,750.0 11,250.0 8 2571 4 62 29,919,235,000 1,805,765,0001,805,776,250.0 11,250.0 8 2570 4 63 29,919,937,500 1,805,062,5001,805,073,750.0 11,250.0 8 2569 4 64 29,920,640,000 1,804,360,0001,804,371,250.0 11,250.0 8 2568 4 65 29,921,342,500 1,803,657,5001,803,668,750.0 11,250.0 8 2567 4 66 29,922,045,000 1,802,955,0001,802,966,250.0 11,250.0 8 2566 4 67 29,922,747,500 1,802,252,5001,802,263,750.0 11,250.0 8 2565 4 68 29,923,450,000 1,801,550,0001,801,561,250.0 11,250.0 8 2564 4 69 29,924,152,500 1,800,847,5001,800,858,750.0 11,250.0 8 2563 4 70 29,924,855,000 1,800,145,0001,800,156,250.0 11,250.0 8 2562 4 71 29,925,557,500 1,799,442,5001,799,453,750.0 11,250.0 8 2561 4 72 29,926,260,000 1,798,740,0001,798,751,250.0 11,250.0 8 2560 4 73 29,926,962,500 1,798,037,5001,798,048,750.0 11,250.0 8 2559 4 74 29,927,665,000 1,797,335,0001,797,346,250.0 11,250.0 8 2558 4 75 29,928,367,500 1,796,632,5001,796,643,750.0 11,250.0 8 2557 4 76 29,929,070,000 1,795,930,0001,795,941,250.0 11,250.0 8 2556 4 77 29,929,772,500 1,795,227,5001,795,238,750.0 11,250.0 8 2555 4 78 29,930,475,000 1,794,525,0001,794,536,250.0 11,250.0 8 2554 4 79 29,931,177,500 1,793,822,5001,793,833,750.0 11,250.0 8 2553 4 80 29,931,880,000 1,793,120,0001,793,131,250.0 11,250.0 8 2552 4 81 29,932,582,500 1,792,417,5001,792,428,750.0 11,250.0 8 2551 4 82 29,933,285,000 1,791,715,0001,791,726,250.0 11,250.0 8 2550 4 83 29,933,987,500 1,791,012,5001,791,023,750.0 11,250.0 8 2549 4 84 29,934,690,000 1,790,310,0001,790,321,250.0 11,250.0 8 2548 4 85 29,935,392,500 1,789,607,5001,789,618,750.0 11,250.0 8 2547 4 86 29,936,095,000 1,788,905,0001,788,916,250.0 11,250.0 8 2546 4 87 29,936,797,500 1,788,202,5001,788,213,750.0 11,250.0 8 2545 4 88 29,937,500,000 1,787,500,0001,787,511,250.0 11,250.0 8 2544 4 89 29,938,202,500 1,786,797,5001,786,808,750.0 11,250.0 8 2543 4 90 29,938,905,000 1,786,095,0001,786,106,250.0 11,250.0 8 2542 4 91 29,939,607,500 1,785,392,5001,785,403,750.0 11,250.0 8 2541 4 92 29,940,310,000 1,784,690,0001,784,701,250.0 11,250.0 8 2540 4 93 29,941,012,500 1,783,987,5001,783,998,750.0 11,250.0 8 2539 4 94 29,941,715,000 1,783,285,0001,783,296,250.0 11,250.0 8 2538 4 95 29,942,417,500 1,782,582,5001,782,593,750.0 11,250.0 8 2537 4 96 29,943,120,000 1,781,880,0001,781,891,250.0 11,250.0 8 2536 4 97 29,943,822,500 1,781,177,5001,781,188,750.0 11,250.0 8 2535 4 98 29,944,525,000 1,780,475,0001,780,486,250.0 11,250.0 8 2534 4 99 29,945,227,500 1,779,772,5001,779,783,750.0 11,250.0 8 2533 4 100 29,945,930,000 1,779,070,0001,779,081,250.0 11,250.0 8 2532 4 101 29,946,632,500 1,778,367,5001,778,378,750.0 11,250.0 8 2531 4 102 29,947,335,000 1,777,665,0001,777,676,250.0 11,250.0 8 2530 4 103 29,948,037,500 1,776,962,5001,776,973,750.0 11,250.0 8 2529 4 104 29,948,740,000 1,776,260,0001,776,271,250.0 11,250.0 8 2528 4 105 29,949,442,500 1,775,557,5001,775,568,750.0 11,250.0 8 2527 4 106 29,950,145,000 1,774,855,0001,774,866,250.0 11,250.0 8 2526 4 107 29,950,847,500 1,774,152,5001,774,163,750.0 11,250.0 8 2525 4 108 29,951,550,000 1,773,450,0001,773,461,250.0 11,250.0 8 2524 4 109 29,952,252,500 1,772,747,5001,772,758,750.0 11,250.0 8 2523 4 110 29,952,955,000 1,772,045,0001,772,056,250.0 11,250.0 8 2522 4 111 29,953,657,500 1,771,342,5001,771,353,750.0 11,250.0 8 2521 4 112 29,954,360,000 1,770,640,0001,770,651,250.0 11,250.0 8 2520 4 113 29,955,062,500 1,769,937,5001,769,948,750.0 11,250.0 8 2519 4 114 29,955,765,000 1,769,235,0001,769,246,250.0 11,250.0 8 2518 4 115 29,956,467,500 1,768,532,5001,768,543,750.0 11,250.0 8 2517 4 116 29,957,170,000 1,767,830,0001,767,841,250.0 11,250.0 8 2516 4 117 29,957,872,500 1,767,127,5001,767,138,750.0 11,250.0 8 2515 4 118 29,958,575,000 1,766,425,0001,766,436,250.0 11,250.0 8 2514 4 119 29,959,277,500 1,765,722,5001,765,733,750.0 11,250.0 8 2513 4 120 29,959,980,000 1,765,020,0001,765,031,250.0 11,250.0 8 2512 4 121 29,960,682,500 1,764,317,5001,764,328,750.0 11,250.0 8 2511 4 122 29,961,385,000 1,763,615,0001,763,626,250.0 11,250.0 8 2510 4 123 29,962,087,500 1,762,912,5001,762,923,750.0 11,250.0 8 2509 4 124 29,962,790,000 1,762,210,0001,762,221,250.0 11,250.0 8 2508 4 125 29,963,492,500 1,761,507,5001,761,518,750.0 11,250.0 8 2507 4 126 29,964,195,000 1,760,805,0001,760,816,250.0 11,250.0 8 2506 4 127 29,964,897,500 1,760,102,5001,760,113,750.0 11,250.0 8 2505 4 128 29,965,600,000 1,759,400,0001,759,411,250.0 11,250.0 8 2504 4 129 29,966,302,500 1,758,697,5001,758,708,750.0 11,250.0 8 2503 4 130 29,967,005,000 1,757,995,0001,758,006,250.0 11,250.0 8 2502 4 131 29,967,707,500 1,757,292,5001,757,303,750.0 11,250.0 8 2501 4 132 29,968,410,000 1,756,590,0001,756,601,250.0 11,250.0 8 2500 4 133 29,969,112,500 1,755,887,5001,755,898,750.0 11,250.0 8 2499 4 134 29,969,815,000 1,755,185,0001,755,196,250.0 11,250.0 8 2498 4 135 29,970,517,500 1,754,482,5001,754,493,750.0 11,250.0 8 2497 4 136 29,971,220,000 1,753,780,0001,753,791,250.0 11,250.0 8 2496 4 137 29,971,922,500 1,753,077,5001,753,088,750.0 11,250.0 8 2495 4 138 29,972,625,000 1,752,375,0001,752,386,250.0 11,250.0 8 2494 4 139 29,973,327,500 1,751,672,5001,751,683,750.0 11,250.0 8 2493 4 140 29,974,030,000 1,750,970,0001,750,981,250.0 11,250.0 8 2492 4 141 29,974,732,500 1,750,267,5001,750,278,750.0 11,250.0 8 2491 4 142 29,975,435,000 1,749,565,0001,749,576,250.0 11,250.0 8 2490 4 143 29,976,137,500 1,748,862,5001,748,873,750.0 11,250.0 8 2489 4 144 29,976,840,000 1,748,160,0001,748,171,250.0 11,250.0 8 2488 4 145 29,977,542,500 1,747,457,5001,747,468,750.0 11,250.0 8 2487 4 146 29,978,245,000 1,746,755,0001,746,766,250.0 11,250.0 8 2486 4 147 29,978,947,500 1,746,052,5001,746,063,750.0 11,250.0 8 2485 4 148 29,979,650,000 1,745,350,0001,745,361,250.0 11,250.0 8 2484 4 149 29,980,352,500 1,744,647,5001,744,658,750.0 11,250.0 8 2483 4 150 29,981,055,000 1,743,945,0001,743,956,250.0 11,250.0 8 2482 4 151 29,981,757,500 1,743,242,5001,743,253,750.0 11,250.0 8 2481 4 152 29,982,460,000 1,742,540,0001,742,551,250.0 11,250.0 8 2480 4 153 29,983,162,500 1,741,837,5001,741,848,750.0 11,250.0 8 2479 4 154 29,983,865,000 1,741,135,0001,741,146,250.0 11,250.0 8 2478 4 155 29,984,567,500 1,740,432,5001,740,443,750.0 11,250.0 8 2477 4 156 29,985,270,000 1,739,730,0001,739,741,250.0 11,250.0 8 2476 4 157 29,985,972,500 1,739,027,5001,739,038,750.0 11,250.0 8 2475 4 158 29,986,675,000 1,738,325,0001,738,336,250.0 11,250.0 8 2474 4 159 29,987,377,500 1,737,622,5001,737,633,750.0 11,250.0 8 2473 4 160 29,988,080,000 1,736,920,0001,736,931,250.0 11,250.0 8 2472 4 161 29,988,782,500 1,736,217,5001,736,228,750.0 11,250.0 8 2471 4 162 29,989,485,000 1,735,515,0001,735,526,250.0 11,250.0 8 2470 4 163 29,990,187,500 1,734,812,5001,734,823,750.0 11,250.0 8 2469 4 164 29,990,890,000 1,734,110,0001,734,121,250.0 11,250.0 8 2468 4 165 29,991,592,500 1,733,407,5001,733,418,750.0 11,250.0 8 2467 4 166 29,992,295,000 1,732,705,0001,732,716,250.0 11,250.0 8 2466 4 167 29,992,997,500 1,732,002,5001,732,013,750.0 11,250.0 8 2465 4 168 29,993,700,000 1,731,300,0001,731,311,250.0 11,250.0 8 2464 4 169 29,994,402,500 1,730,597,5001,730,608,750.0 11,250.0 8 2463 4 170 29,995,105,000 1,729,895,0001,729,906,250.0 11,250.0 8 2462 4 171 29,995,807,500 1,729,192,5001,729,203,750.0 11,250.0 8 2461 4 172 29,996,510,000 1,728,490,0001,728,501,250.0 11,250.0 8 2460 4 173 29,997,212,500 1,727,787,5001,727,798,750.0 11,250.0 8 2459 4 174 29,997,915,000 1,727,085,0001,727,096,250.0 11,250.0 8 2458 4 175 29,998,617,500 1,726,382,5001,726,393,750.0 11,250.0 8 2457

TABLE 6 Tuning Commands for Class B - Band 1 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 1 1 29,502,787,500 2,222,212,5002,222,241,666.7 29,166.7 16 948 1 2 29,506,300,000 2,218,700,0002,218,729,166.7 29,166.7 8 947 1 3 29,509,812,500 2,215,187,5002,215,216,666.7 29,166.7 16 945 1 4 29,513,325,000 2,211,675,0002,211,704,166.7 29,166.7 8 944 1 5 29,516,837,500 2,208,162,5002,208,191,666.7 29,166.7 16 942 1 6 29,520,350,000 2,204,650,0002,204,679,166.7 29,166.7 8 941 1 7 29,523,862,500 2,201,137,5002,201,166,666.7 29,166.7 16 939 1 8 29,527,375,000 2,197,625,0002,197,654,166.7 29,166.7 8 938 1 9 29,530,887,500 2,194,112,5002,194,141,666.7 29,166.7 16 936 1 10 29,534,400,000 2,190,600,0002,190,629,166.7 29,166.7 8 935 1 11 29,537,912,500 2,187,087,5002,187,116,666.7 29,166.7 16 933 1 12 29,541,425,000 2,183,575,0002,183,604,166.7 29,166.7 8 932 1 13 29,544,937,500 2,180,062,5002,180,091,666.7 29,166.7 16 930 1 14 29,548,450,000 2,176,550,0002,176,579,166.7 29,166.7 8 929 1 15 29,551,962,500 2,173,037,5002,173,066,666.7 29,166.7 16 927 1 16 29,555,475,000 2,169,525,0002,169,554,166.7 29,166.7 8 926 1 17 29,558,987,500 2,166,012,5002,166,041,666.7 29,166.7 16 924 1 18 29,562,500,000 2,162,500,0002,162,529,166.7 29,166.7 8 923 1 19 29,566,012,500 2,158,987,5002,159,016,666.7 29,166.7 16 921 1 20 29,569,525,000 2,155,475,0002,155,504,166.7 29,166.7 8 920 1 21 29,573,037,500 2,151,962,5002,151,991,666.7 29,166.7 16 918 1 22 29,576,550,000 2,148,450,0002,148,479,166.7 29,166.7 8 917 1 23 29,580,062,500 2,144,937,5002,144,966,666.7 29,166.7 16 915 1 24 29,583,575,000 2,141,425,0002,141,454,166.7 29,166.7 8 914 1 25 29,587,087,500 2,137,912,5002,137,941,666.7 29,166.7 16 912 1 26 29,590,600,000 2,134,400,0002,134,429,166.7 29,166.7 8 911 1 27 29,594,112,500 2,130,887,5002,130,916,666.7 29,166.7 16 909 1 28 29,597,625,000 2,127,375,0002,127,404,166.7 29,166.7 8 908 1 29 29,601,137,500 2,123,862,5002,123,891,666.7 29,166.7 16 906 1 30 29,604,650,000 2,120,350,0002,120,379,166.7 29,166.7 8 905 1 31 29,608,162,500 2,116,837,5002,116,866,666.7 29,166.7 16 903 1 32 29,611,675,000 2,113,325,0002,113,354,166.7 29,166.7 8 902 1 33 29,615,187,500 2,109,812,5002,109,841,666.7 29,166.7 16 900 1 34 29,618,700,000 2,106,300,0002,106,329,166.7 29,166.7 8 899 1 35 29,622,212,500 2,102,787,5002,102,816,666.7 29,166.7 16 897

TABLE 7 Tuning Commands for Class B - Band 2 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 2 1 29,627,787,500 2,097,212,5002,097,255,208.3 42,708.3 10 895 2 2 29,631,300,000 2,093,700,0002,093,742,708.3 42,708.3 2 894 2 3 29,634,812,500 2,090,187,5002,090,230,208.3 42,708.3 10 892 2 4 29,638,325,000 2,086,675,0002,086,717,708.3 42,708.3 2 891 2 5 29,641,837,500 2,083,162,5002,083,205,208.3 42,708.3 10 889 2 6 29,645,350,000 2,079,650,0002,079,692,708.3 42,708.3 2 888 2 7 29,648,862,500 2,076,137,5002,076,180,208.3 42,708.3 10 886 2 8 29,652,375,000 2,072,625,0002,072,667,708.3 42,708.3 2 885 2 9 29,655,887,500 2,069,112,5002,069,155,208.3 42,708.3 10 883 2 10 29,659,400,000 2,065,600,0002,065,642,708.3 42,708.3 2 882 2 11 29,662,912,500 2,062,087,5002,062,130,208.3 42,708.3 10 880 2 12 29,666,425,000 2,058,575,0002,058,617,708.3 42,708.3 2 879 2 13 29,669,937,500 2,055,062,5002,055,105,208.3 42,708.3 10 877 2 14 29,673,450,000 2,051,550,0002,051,592,708.3 42,708.3 2 876 2 15 29,676,962,500 2,048,037,5002,048,080,208.3 42,708.3 10 874 2 16 29,680,475,000 2,044,525,0002,044,567,708.3 42,708.3 2 873 2 17 29,683,987,500 2,041,012,5002,041,055,208.3 42,708.3 10 871 2 18 29,687,500,000 2,037,500,0002,037,542,708.3 42,708.3 2 870 2 19 29,691,012,500 2,033,987,5002,034,030,208.3 42,708.3 10 868 2 20 29,694,525,000 2,030,475,0002,030,517,708.3 42,708.3 2 867 2 21 29,698,037,500 2,026,962,5002,027,005,208.3 42,708.3 10 865 2 22 29,701,550,000 2,023,450,0002,023,492,708.3 42,708.3 2 864 2 23 29,705,062,500 2,019,937,5002,019,980,208.3 42,708.3 10 862 2 24 29,708,575,000 2,016,425,0002,016,467,708.3 42,708.3 2 861 2 25 29,712,087,500 2,012,912,5002,012,955,208.3 42,708.3 10 859 2 26 29,715,600,000 2,009,400,0002,009,442,708.3 42,708.3 2 858 2 27 29,719,112,500 2,005,887,5002,005,930,208.3 42,708.3 10 856 2 28 29,722,625,000 2,002,375,0002,002,417,708.3 42,708.3 2 855 2 29 29,726,137,500 1,998,862,5001,998,905,208.3 42,708.3 10 853 2 30 29,729,650,000 1,995,350,0001,995,392,708.3 42,708.3 2 852 2 31 29,733,162,500 1,991,837,5001,991,880,208.3 42,708.3 10 850 2 32 29,736,675,000 1,988,325,0001,988,367,708.3 42,708.3 2 849 2 33 29,740,187,500 1,984,812,5001,984,855,208.3 42,708.3 10 2847 2 34 29,743,700,000 1,981,300,0001,981,342,708.3 42,708.3 2 846 2 35 29,747,212,500 1,977,787,5001,977,830,208.3 42,708.3 10 844

TABLE 8 Tuning Commands for Class B - Band 3 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 3 1 29,752,787,500 1,972,212,5001,972,268,750.0 56,250.0 4 842 3 2 29,756,300,000 1,968,700,0001,968,756,250.0 56,250.0 12 840 3 3 29,759,812,500 1,965,187,5001,965,243,750.0 56,250.0 4 839 3 4 29,763,325,000 1,961,675,0001,961,731,250.0 56,250.0 12 837 3 5 29,766,837,500 1,958,162,5001,958,218,750.0 56,250.0 4 836 3 6 29,770,350,000 1,954,650,0001,954,706,250.0 56,250.0 12 834 3 7 29,773,862,500 1,951,137,5001,951,193,750.0 56,250.0 4 833 3 8 29,777,375,000 1,947,625,0001,947,681,250.0 56,250.0 12 831 3 9 29,780,887,500 1,944,112,5001,944,168,750.0 56,250.0 4 830 3 10 29,784,400,000 1,940,600,0001,940,656,250.0 56,250.0 12 288 3 11 29,787,912,500 1,937,087,5001,937,143,750.0 56,250.0 4 827 3 12 29,791,425,000 1,933,575,0001,933,631,250.0 56,250.0 12 825 3 13 29,794,937,500 1,930,062,5001,930,118,750.0 56,250.0 4 824 3 14 29,798,450,000 1,926,550,0001,926,606,250.0 56,250.0 12 822 3 15 29,801,962,500 1,923,037,5001,923,093,750.0 56,250.0 4 821 3 16 29,805,475,000 1,919,525,0001,919,581,250.0 56,250.0 12 819 3 17 29,808,987,500 1,916,012,5001,916,068,750.0 56,250.0 4 818 3 18 29,812,500,000 1,912,500,0001,912,556,250.0 56,250.0 12 816 3 19 29,816,012,500 1,908,987,5001,909,043,750.0 56,250.0 4 815 3 20 29,819,525,000 1,905,475,0001,905,531,250.0 56,250.0 12 813 3 21 29,823,037,500 1,901,962,5001,902,018,750.0 56,250.0 4 812 3 22 29,826,550,000 1,898,450,0001,898,506,250.0 56,250.0 12 810 3 23 29,830,062,500 1,894,937,5001,894,993,750.0 56,250.0 4 809 3 24 29,833,575,000 1,891,425,0001,891,481,250.0 56,250.0 12 807 3 25 29,837,087,500 1,887,912,5001,887,968,750.0 56,250.0 4 806 3 26 29,840,600,000 1,884,400,0001,884,456,250.0 56,250.0 12 804 3 27 29,844,112,500 1,880,887,5001,880,943,750.0 56,250.0 4 803 3 28 29,847,625,000 1,877,375,0001,877,431,250.0 56,250.0 12 801 3 29 29,851,137,500 1,873,862,5001,873,918,750.0 56,250.0 4 800 3 30 29,854,650,000 1,870,350,0001,870,406,250.0 56,250.0 12 798 3 31 29,858,162,500 1,866,837,5001,866,893,750.0 56,250.0 4 797 3 32 29,861,675,000 1,863,325,0001,863,381,250.0 56,250.0 12 795 3 33 29,865,187,500 1,859,812,5001,859,868,750.0 56,250.0 4 794 3 34 29,868,700,000 1,856,300,0001,856,356,250.0 56,250.0 12 792 3 35 29,872,212,500 1,852,787,5001,852,843,750.0 56,250.0 4 791

TABLE 9 Tuning Commands for Class B - Band 4 Channel Transmit TransmitCenter Offset Channel Channel Frequency f_(IF) f_(VCO,IF) Frequency BandNumber (Hz) (Hz) (Hz) (Hz) F N 4 1 29,877,787,500 1,847,212,5001,847,282,291.7 69,791.7 14 788 4 2 29,881,300,000 1,843,700,0001,843,769,791.7 69,791.7 6 787 4 3 29,884,812,500 1,840,187,5001,840,257,291.7 69,791.7 14 785 4 4 29,888,325,000 1,836,675,0001,836,744,791.7 69,791.7 6 784 4 5 29,891,837,500 1,833,162,5001,833,232,291.7 69,791.7 14 782 4 6 29,895,350,000 1,829,650,0001,829,719,791.7 69,791.7 6 781 4 7 29,898,862,500 1,826,137,5001,826,207,291.7 69,791.7 14 779 4 8 29,902,375,000 1,822,625,0001,822,694,791.7 69,791.7 6 778 4 9 29,905,887,500 1,819,112,5001,819,182,291.7 69,791.7 14 776 4 10 29,909,400,000 1,815,600,0001,815,669,791.7 69,791.7 6 775 4 11 29,912,912,500 1,812,087,5001,812,157,291.7 69,791.7 14 773 4 12 29,916,425,000 1,808,575,0001,808,644,791.7 69,791.7 6 772 4 13 29,919,937,500 1,805,062,5001,805,132,291.7 69,791.7 14 770 4 14 29,923,450,000 1,801,550,0001,801,619,791.7 69,791.7 6 769 4 15 29,926,962,500 1,798,037,5001,798,107,291.7 69,791.7 14 767 4 16 29,930,475,000 1,794,525,0001,794,594,791.7 69,791.7 6 766 4 17 29,933,987,500 1,791,012,5001,791,082,291.7 69,791.7 14 764 4 18 29,937,500,000 1,787,500,0001,787,569,791.7 69,791.7 6 763 4 19 29,941,012,500 1,783,987,5001,784,057,291.7 69,791.7 14 761 4 20 29,944,525,000 1,780,475,0001,780,544,791.7 69,791.7 6 760 4 21 29,948,037,500 1,776,962,5001,777,032,291.7 69,791.7 14 758 4 22 29,951,550,000 1,773,450,0001,773,519,791.7 69,791.7 6 757 4 23 29,955,062,500 1,769,937,5001,770,007,291.7 69,791.7 14 755 4 24 29,958,575,000 1,766,425,0001,766,494,791.7 69,791.7 6 754 4 25 29,962,087,500 1,762,912,5001,762,982,291.7 69,791.7 14 752 4 26 29,965,600,000 1,759,400,0001,759,469,791.7 69,791.7 6 751 4 27 29,969,112,500 1,755,887,5001,755,957,291.7 69,791.7 14 749 4 28 29,972,625,000 1,752,375,0001,752,444,791.7 69,791.7 6 748 4 29 29,976,137,500 1,748,862,5001,748,932,291.7 69,791.7 14 746 4 30 29,979,650,000 1,745,350,0001,745,419,791.7 69,791.7 6 745 4 31 29,983,162,500 1,741,837,5001,741,907,291.7 69,791.7 14 743 4 32 29,986,675,000 1,738,325,0001,738,394,791.7 69,791.7 6 742 4 33 29,990,187,500 1,734,812,5001,734,882,291.7 69,791.7 14 740 4 34 29,993,700,000 1,731,300,0001,731,369,791.7 69,791.7 6 739 4 35 29,997,212,500 1,727,787,5001,727,857,291.7 69,791.7 14 737

As can been seen in the tables above, the maximum offset frequency fromthe NCO (300) in either class A or class B systems is less than 70 kHzwhich is much smaller than either of the 702.5 kHz or 3.5125 MHz channelbandwidths for class A or class B, respectively. These offsets differfor each band (500 a–d; FIG. 5), but are fixed within a given band(e.g., 500 a; FIG. 5).

After producing the frequency offset that is needed for a desiredfrequency step size, the NCO (300) will change the frequency offsetslightly to compensate for the Doppler effect in each band (500 a–d;FIG. 5).

Finally, the components labeled as (306) in FIG. 3 are part of the IDU(100). A detailed description of their functionality will not be given.They may or may not be needed in two-way satellite communicationsystems. As can be seen in FIG. 3 as well, a phase lock loop (PLL) (307)generates the reference frequency, f_(REF), that is used by thecomponents of the ODU (106).

The preceding description has been presented only to illustrate anddescribe the invention. It is not intended to be exhaustive or to limitthe invention to any precise form disclosed. Many modifications andvariations are possible in light of the above teaching.

The preferred embodiment was chosen and described in order to bestexplain the principles of the invention and its practical application.The preceding description is intended to enable others skilled in theart to best utilize the invention in various embodiments and withvarious modifications as are suited to the particular use contemplated.It is intended that the scope of the invention be defined by thefollowing claims.

1. A modulation system for modulating data onto a carrier signal in aplurality of channels, each of said channels having a channel bandwidth,said system comprising: a digital modulator outputting a modulatedbaseband signal; an intermediate frequency modulator that receives saidmodulated baseband signal and outputs an intermediate frequency signalderived from said modulated baseband signal; a frequency synthesizingsystem outputting a synthesized intermediate frequency signal to saidintermediate frequency modulator; and a circuit connected to saiddigital modulator, said circuit providing a signal to said digitalmodulator, said signal having a frequency including an offset thatallows said frequency synthesizing system and intermediate frequencymodulator to make frequency steps equal to said channel bandwidth,wherein said circuit comprises a numerically controlled oscillator andsaid numerically controlled oscillator receives a data signal, saidoffset being based on said data signal.
 2. The system of claim 1,wherein said modulation system is incorporated in a two-way satellitecommunication system and said data signal is received from a satellite.3. The system of claim 1, wherein said frequency synthesizing system iscomprised of two frequency synthesizers.
 4. The system of claim 3,wherein said frequency synthesizers are configured in a ping-pongconfiguration, said frequency synthesizing system further comprising aswitch connected between said two frequency synthesizers and saidintermediate frequency modulator, said switch selectively connectingsaid intermediate frequency modulator with one of said frequencysynthesizers.
 5. The system of claim 1, wherein each of said frequencysynthesizing system comprises a programmable circuit for controlling afrequency output of said frequency synthesizing system.
 6. The system ofclaim 1, wherein said frequency synthesizing system comprises a bank offilters for filtering spurious noise of said synthesized intermediatefrequency signal.
 7. The system of claim 1, wherein said circuitconnected to said digital modulator further provides said signal to saiddigital modulator, said signal having a frequency including anadditional offset that compensates for Doppler effect in transmission ofsaid carrier signal.
 8. A modulation system for modulating data onto acarrier signal in a plurality of channels, each of said channels havinga channel bandwidth, said system comprising: a digital modulatoroutputting a modulated baseband signal; an intermediate frequencymodulator that receives said modulated baseband signal and outputs anintermediate frequency signal derived from said modulated basebandsignal; a frequency synthesizing system outputting a synthesizedintermediate frequency signal to said intermediate frequency modulator;and a circuit connected to said digital modulator, said circuitproviding a signal to said digital modulator, said signal having afrequency including an offset that compensates for Doppler effect intransmission of said carrier signal, wherein said circuit comprises anumerically controlled oscillator and said numerically controlledoscillator receives a data signal, said offset being based on said datasignal.
 9. The system of claim 8, wherein said modulation system isincorporated in a two-way satellite communication system and said datasignal is received from a satellite.
 10. The system of claim 8, whereinsaid frequency synthesizing system is comprised of two frequencysynthesizers.
 11. The system of claim 10, wherein said frequencysynthesizers are configured in a ping-pong configuration, said frequencysynthesizing system further comprising a switch connected between saidtwo frequency synthesizers and said intermediate frequency modulator,said switch selectively connecting said intermediate frequency modulatorwith one of said frequency synthesizers.
 12. The system of claim 8,wherein each of said frequency synthesizing system comprises aprogrammable circuit for controlling a frequency output of saidfrequency synthesizing system.
 13. The system of claim 8, wherein saidfrequency synthesizing system comprises a bank of filters for filteringspurious noise of said synthesized intermediate frequency signal. 14.The system of claim 8, wherein said circuit connected to said digitalmodulator further provides said signal to said intermediate frequencymodulator, said signal having a frequency including an additional offsetthat allows said frequency synthesizing system and intermediatefrequency modulator to make frequency steps equal to said channelbandwidth.
 15. A method for modulating data onto a carrier signal in aplurality of channels, each of said channels having a channel bandwidth,said method comprising: providing a signal to a digital modulator thatmodulates a baseband signal, said signal having a frequency including anoffset that allows a frequency synthesizing system and intermediatefrequency modulator to make frequency steps equal to said channelbandwidth; generating said signal including said offset with anumerically controlled oscillator; and inputting a data signal to saidnumerically controlled oscillator, wherein said numerically controlledoscillator generates said offset based on said data signal.
 16. Themethod of claim 15, further comprising receiving said data signal from asatellite in a two-way satellite communication system.
 17. The method ofclaim 15, wherein said frequency synthesizing system comprises aprogrammable circuit for controlling a frequency output of saidfrequency synthesizing system, said method further comprisingprogramming said programmable circuit.
 18. The method of claim 15,further comprising generating said signal with a frequency including anadditional offset that compensates for Doppler effect in transmission ofsaid carrier signal.
 19. A method of modulating data onto a carriersignal in a plurality of channels, each of said channels having achannel bandwidth, said method comprising: providing a signal to adigital modulator that modulates a baseband signal, said signal having afrequency including an offset that compensates for Doppler effect intransmission of said carrier signal; generating said signal includingsaid offset with a numerically controlled oscillator; and inputting adata signal to said numerically controlled oscillator, wherein saidnumerically controlled oscillator generates said offset based on saiddata signal.
 20. The method of claim 19, further comprising receivingsaid data signal from a satellite in a two-way satellite communicationsystem.
 21. The method of claim 19, further comprising generating saidsignal with a frequency including an additional offset that allows afrequency synthesizing system and intermediate frequency modulator tomake frequency steps equal to said channel bandwidth.
 22. A system formodulating data onto a carrier signal in a plurality of channels, eachof said channels having a channel bandwidth, said system comprising: adigital modulator outputting a modulated baseband signal; anintermediate frequency modulator that receives said modulated basebandsignal and outputs an intermediate frequency signal derived from saidmodulated baseband signal; a frequency synthesizing system outputting asynthesized intermediate frequency signal to said intermediate frequencymodulator; and means for generating a signal input to said digitalmodulator, said signal having a frequency including an offset thatallows said frequency synthesizing system and said intermediatefrequency modulator to make frequency steps equal to said channelbandwidth, said means for generating said signal including a numericallycontrolled oscillator; and means for inputting a data signal to saidnumerically controlled oscillator, wherein said numerically controlledoscillator generates said offset based on said data signal.
 23. Thesystem of claim 22, further comprising means for receiving said datasignal from a satellite in a two-way satellite communication system. 24.The system of claim 22, wherein said frequency synthesizing systemcomprises programmable means for controlling a frequency output of saidfrequency synthesizing system.
 25. The system of claim 22, furthercomprising means for generating said signal with a frequency includingan additional offset that compensates for Doppler effect in transmissionof said carrier signal.
 26. A system for modulating data onto a carriersignal in a plurality of channels, each of said channels having achannel bandwidth, said system comprising: a digital modulatoroutputting a modulated baseband signal; an intermediate frequencymodulator that receives said modulated baseband signal and outputs anintermediate frequency signal derived from said modulated basebandsignal; a frequency synthesizing system outputting a synthesizedintermediate frequency signal to said intermediate frequency modulator;means for generating a signal input to said digital modulator, saidsignal having a frequency including an offset that compensates forDoppler effect in transmission of said carrier signal, said means forgenerating said signal including a numerically controlled oscillator;and means for inputting a data signal to said numerically controlledoscillator, wherein said numerically controlled oscillator generatessaid offset based on said data signal.
 27. The system of claim 26,further comprising means for receiving said data signal from a satellitein a two-way satellite communication system.
 28. The system of claim 26,wherein said frequency synthesizing system comprises programmable meansfor controlling a frequency output of said frequency synthesizingsystem.
 29. The system of claim 26, further comprising means forgenerating said signal with a frequency including an additional offsetthat allows said frequency synthesizing system and said intermediatefrequency modulator to make frequency steps equal to said channelbandwidth.